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Status report: Linkage between technology and science
237
Status report: Linkage between technology and science Francis
Narin
and
Dominic
Olivastro
CHI Research Inc., 10 White Horse Pike, Haddon Heights NJ 08035, USA Final version
received
May 199 1
A status report is presented on indicators of the linkage between technology, as characterized by granted U.S. patents, and science as characterized by the “Other references” cited on the front page of those patents. It is shown that these other references have increased threefold in recent years from fewer than one-third per patent in 1975 to more than one per patent in 1989. These science linkages occur most heavily in pharmaceutical, chemical and electronics patents; the cited science is youngest in electronics and pharmaceuticals with a median age of three to four years, similar to the age of research papers cited in other research papers. The cited science varies significantly for patents in the different major countries, at least partially reflecting the national differences in technological emphasis, including the strong electronic emphasis for Japanese patenting, and the U.S. and U.K. strengths in pharmaceuticals.
1. Introduction It has long been perceived that there is a continuum stretching from very basic scientific research, through applied research and technology, to economic growth and national prosperity. In his 1965 paper entitled “Is Technology Historically Independent of Science? A Study in Historiography” [5] the late Derek de Solla Price quoted Toynbee’s description that “physical science and industrialism may be conceived of as a pair of dancers, both of whom know their steps, and have an ear for the rhythm of the music. If the partner who has been leading chooses to change parts and to follow instead, there is perhaps no reason to expect that he will dance less correctly than before” [ 131.
Thus the close linkage and feedback between the scientific, industrial and technological communities has been long recognized. Moreover, the key role that this linkage has played in the development of the economies of the West has been clearly called out by Rosenberg and Birdzell who, in a recent article “Science, Technology, and the Western Miracle” point out that “close links between the growth of scientific knowledge and the rise of technology have permitted the market economies of the western nations to achieve unprecedented prosperity” [ 121. Yet, with all of this qualitative understanding of linkage, there has been very little quantitative data to specifically characterize this relationship, or to pinpoint the subject, national and temporal aspects of the coupling between technology and science. Fortunately, the “Other references” cited in U.S. patents provide a means for directly measuring this link. This paper presents and updates data from a series of studies that CHI Research, Inc. (CHI) has been carrying out over the last ten years, to directly measure the relationship between technology and science. All of these studies have centered around use of the references in U.S. patents, especially the front page or examiner “Other references” cited. CHI’s studies have both counted and characterized these references, and used them to establish the links between the technology embodied in the patent, and the scientific research upon which it is dependent.
2. Earlier studies The first of these studies, “Linkage between Basic Research Literature and Patents”, looked
Research Policy 21 (1992) 237-249 North-Holland 0048-7333/92/$05.00
0 1992
Elsevier
Science
Publishers
B.V. All rights reserved
F. Narirl und D. Olil,astro / Lmkuge
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at the referencing in the mid-1970s in two of the most rapidly growing areas of U.S. patenting, gas lasers and prostaglandins [3]. Gas lasers were selected because of their growing application in many areas of technology, and prostaglandins because of their very significant medical potential. It was found that the patents in those two very scientific areas of technology contain many citations to the scientific literature, 10 per patent for prostaglandins and two to three per patent for gas lasers. Further, it was shown that close to 90% of all of the journal references are to either basic or applied scientific journals, as opposed to engineering journals or to the technological literature. It was also found that the time between the publication of a journal article and the patent citing that article was relatively short, generally three to five years, which is quite similar to the amount of time that elapses between the publication of a scientific article and its citation by other scientific articles. It was concluded that this evidence “clearly indicates that the process of reduction to practice in the industrial community continues to require recent science, and the sup-
Table I Citations
to science
from U.S. patents, Number patents ”
Other references per patent
Journal ref per patent
1 2 3 15 16 17 1X 21 22 33 44 55 56
4750 4277 72857 5348 20768 963 1 5253 46191 114071 74153 26813 49880 30743
0.62 0.26 0.68 0.15 0.13 0.13 0.21 0.06 0.07 0.22 0.03 0.23 0.06
3X3292
All ’ Product
nnd .scirnce
port of such science is a necessary prerequisite for the continuing emergence of new technology.” Three subsequent CHI documents expanded upon and generalized that first finding of strong linkage between technology and science. In the first of these, a validation study of patent citations as indicators of both science and foreign dependence, we formally tested whether the number of front page, examiner citations per patent to the scientific literature corresponded to peer rankings of the science dependence of the technologies [2]. A total of 24 technologies were chosen for this, 12 of which were judged in advance to be science-dependent and 12 judged in advance to be foreign-dependent. A peer group of 19 high level R&D managers was asked to rank these technologies in terms of both their science and foreign dependence. The bibliometric rankings were then compared with the peer ranks. A high degree of agreement was found between the expert opinions and the corresponding bibliometric rankings. For example, the eight technologies judged most science-dependent by experts averaged 0.92 examiner citations per
197551980
Major product group
Food Kind. Prod. Textile Mill Pro Chem. Allied Pro Petroleum Nat. Rubber & Misc. Stone, Clay, Gl Primary Metals Fab. Metal Prod Mach., Expt. El Electr. & Elect Transporta. Eq. Profess. 6t Scie Unclassified
hetwrerz technology
Number
of references
to
Average level
Applied technology
Engineering science
Applied research
Basic research
0.28 0.1 1 0.31 0.07 0.05 0.05 0.09 0.03 0.03 0.12 0.01 0.15 0.02
(LVI) 70 202 780 95 160 SO 80 151 789 1489 6X 876 283
(LV2) 200 81 1586 59 243 162 107 21s 722 2437 44 1288 78
(LV3) 315 61 5077 48 413 129 110 407 458 2732 13 2801 77
(LV4l 627 44 13740 49 82 39 52 91 250 638 19 1260 63
3.2 1.9 3.5 2.2 2.5 2.4 2.4 2.5 2.1 2.4 1.9 2.7 1.8
0.23
0.11
4326
6256
11017
15754
3
I.7734 11857
1.OJ 1.01
0.5 0.42
175 132
538 373
2007 1304
3646 279X
3.4 3.5
31654
0.78
0.39
287
467
I977
X923
3.7
subgroups
Drugs, medicines Agricultural chemicals Industrial Organic Chemicals
’ Some patents are classified into more than one product h The “All” line counts the references from these patents
group only once
F. Narin and D. Olic~astro / Linkage between technology and science
patent to scientific journal literature, while the eight technologies judged least science-dependent had only 0.05 citations per patent to journal papers. These findings thus provided support for the hypothesis that the technology-to-science linkage was much broader than just for the two technologies studied in CHI’s first paper. The magnitude and direction of this linkage was further developed and reported in a paper presented at the American Association for the Advancement of Science meeting in May of 1983 [I]. That data is summarized in table 1. The classification is based on the U.S. patent office’s initial concordance between patent classification and Product Fields based on the U.S. Standard Industrial Classification (SIC) ill]. The citations were obtained from the unification of all of the references from the front page of essentially all U.S. patents issued between 1975 and 1980. The number of these citations to technical and scientific literature was tabulated. The number of these references per patent is relatively modest, 0.23; the literature references are approximately half, 0.11 per patent to journals. However, in such specific product fields as drugs and medicine, agricultural chemistry and industrial organic
Table 2 Citations
to six major fields of science,
Number other refs ”
1 2 3 15 I6 17 18 21 22 33 44 55 56
1202 388 21023 248 893 376 348 850 2184 7185 134 6159 496
All h Product subgroups Drugs. medicines Agricultural chemicals Industrial organic chemicals
Food Kind. Prod. Textile Mill Pro Chem. Allied Pro Petroleum Nat. Rubber & misc. Stone. Clay, Gl Primary Metals Fab. Metal Prod Mach., Expt. El Electr. & Elect Transporta. Eq. Profess. & Scie Unclassified
chemistry the figures are rather considerably higher, and they are of course, very low in transportation equipment, and other mechanically, rather than scientifically, related fields. A further interesting observation is that many of the journal references are to relatively basic journals. On CHI’s research level scale the most basic journals are in Basic Research (Level 41, followed by Applied Research (Level 3), Engineering Science (Levels 2), and Applied Technology (Level l)[lO]. Table 1 also shows the level distribution of papers cited from each of those product groups. It is clear that for most of the fields the average level is weighted toward applied research, with only one third or fewer papers in applied technology and engineering science. In particular, patents in chemistry and allied products, which include drugs and medicines, heavily cite basic research journals. The scientific papers cited on the front pages of U.S. patents are published largely in basic and applied research journals. The fields of science cited by these 1975 to 1980 patents, summarized in table 2, are also interesting and revealing. The major contrasts are between electrical and electronics, for which the
1975-1980
group
Major product
239
Percent
of these references
to
Clinical medicine
Biomedical research
Biology
Chemistry
Physics
Engineering
16 19 0 3 1 1 3 4 3 1 24 10
36 1 12 2 1 2 1 2 5 5 1 15 4
29 0 3 0 0 1 0 1 4 0 1 1 2
14 24 59 36 28 24 14 22 12 8 9 15 17
0 4 1 3 28 19 24 33 13 35 7 29 7
4 70 6 59 52 53 62 38 62 49 80 I6 60
36972
14
9
3
39
13
21
6322 4574 11602
39 31 11
18 I7 7
4 8 2
39 43 74
0 0
1 1 5
I
” Some patents are classified into more than one product group h The All line counts the references from these patents only once
I
240
F. Narin and Il. Olimstro
/ Linkage hetweerz technology and .scicwce
great majority of references, approximately 75% are to physics and engineering journals, and chemistry and allied products with only 7% of the science references to physics and engineering. Appropriately, food and kindred products cites to the biological literature more heavily than any other product group, and also cites to biomedicine and chemistry. Chemical and allied products cites, of course, largely to chemistry, but also to clinical medicine and biomedical research, but that is partially due to the fact that the drug and medicine classes are included, in the upper part of the table, in the chemical and allied product major product groups. An interesting balance is shown by professional and scientific instruments, which cites quite heavily both to clinical medicine and biomedical research, and also to physics and engineering. If one looks at the patents that are contained in this product group, they span the whole area of instrumentation from medical instrumentation to lasers for physics and enginecring applications, and the science cited by these product groups shows its dependence and linkage to those two major classes of application, biomedical and industrial. The more precise product subgroups shown at the bottom part of the table further show these trends, with drugs and medicine giving almost 60% of its references to clinical medical and biomedical research, and most of the rest to chemistry, while industrial organic chemistry has 75% of its references to chemistry. Agricultural chemicals, which includes many biologically active compounds which are cross classified into drugs and medicine, is much more evenly split in its science dependence on both chemistry and the biomedical fields. In fact, the subjectively appropriate nature of these linkages is a kind of dual validation: it both shows that the kind of science that one knows is relevant to those technologies is cited by them, and it also indicates that the concordance created by the patent office has, in fact, quite well categorized the patents into technologies that have similar scientific and engineering dependencies. A further step in understanding the relationship between technology and science was embodied in a subsequent paper, “Is Technology Bein which citation and referenccoming Science?“, ing data from recent biotechnology patents and biosciences papers were analyzed. [6] Specifically,
in that paper it was shown that the time distribution of references from both patents and papers are similar, with a peak in the citation distribution at two to four years prior to the publication of the paper or issue of the patent. This two to four year lag was essentially the same for patents citing patents, for papers citing papers, and for patents citing papers. From that we concluded that science and technology are very closely linked, and that, in fact, the division between leading edge biotechnology and modern science has almost completely disappeared. This corresponds in a very quantitative way to the observation, in our first linkage paper, that reading the prostaglandin patent was very similar to reading a scientific paper. The arrangement of the materials was slightly different, but the content was virtually identical. A patent in that highly science-dependent area was virtually identical in substance to a scientific paper in the same area, and had the same referencing and other characteristics. One additional set of data has recently been published summarizing some of the overall trends in science linkage, namely the aggregate trend in number of “Other references” cited on the front pages of U.S. patents from 1975 to 1985, and the trends in the median age of these references. [71 In that paper it was shown that the number of these other references had increased from approximately 0.2 per U.S. patent in 1975 to between 0.3 and 0.8, depending on the country, ten years later. The median age of those references has decreased dramatically, by one to two years, for most of the major countries studied, with the median age of references cited in U.S.-invented U.S. patents only 6.5 years, and Japanese-invented patents less than 7 years. That data, however, looked at all of the patents of five major technological powers, the U.S., Japan, West Germany, France, and the United Kingdom in the aggregate, and did not account for the significant differences in patent emphasis of the countries. The differences seen between the countries, with Japanese-invented U.S. patents having the smallest science-dependence and the U.S. the largest, are at least partially due to the relatively heavy U.S. emphasis on pharmaceuticals, a particularly science-dependent area, as opposed to the Japanese emphasis on electronics, a moderately science-dependent area. Similarly, the relatively
F. Narin and D. Olirastro / Linkage between technology and science
old median age of the references in the German invented patents, some one to two years older than the average reference cited in a Japanese or a U.S. invented patent, is almost certainly due to the very heavy emphasis of German technology on traditional areas of mechanical and chemical technology. The data presented in the next section of this paper will separate out these effects of product field emphasis and national emphasis. Two additional recent studies of linkage should be mentioned, as they provided further data about the linkage between technology and research. Collins and Wyatt [4] reported on citations in patents to the basic research literature, focusing on the linkage between genetics technology, as contained in 366 genetics patents issued in the U.S. system in the early 1980s and the research cited both by the examiners and by the applicants in those patents. They extracted both the examiner references from the front pages, and the applicant references in the text of the patents, unified them, traced them to the underlying scientific papers, and looked at characteristics of the linkage. Amongst their key observations were that the peak of citations was to very young papers, aged two to three years, corresponding, as has been seen in other data, to a time lag between technology and science which is no longer than the time lag between scientific papers and successor papers. They also found that the general characteristics of the citations from both examiner and applicant were quite similar; in both cases 80% or so of the citations were to very basic, Level 4 research journals. Finally, they found that there were perceptible differences in the country to country linkages, with a clear tendency for a given country’s patents to cite research papers from the same country. However, over and above this, the citation performance of U.K. papers in genetics was found to be very strong, with a disproportionate U.K. representation in the highly cited papers, and almost 12% of all of the science cited in genetics technology originating in the U.K. The U.K.‘s performance in genetics research, as indicated by these citations was characterized as “in both absolute and relative terms . . . the U.K. produces significantly more papers that are useful to patenters than FRG, France or Japan” (p. 72).
241
In another study of the science base of recent technology Van Vianen et al. [14] at the University of Leiden used the references in U.S. patents to identify the science base of recent technological developments. They studied two data sets, all 1985 U.S. patents in the field of chemical techand pharmaceuticals, and all nology Netherlands-invented U.S. patents for all fields of technology for the period 1982-1985. They found that the field of pharmaceuticals uses relatively young science, whereas the chemical technology subfield of organic compounds uses relatively old science. They also found that the journals cited in patent references show a remarkable parallel with the distribution of journals cited in the serial literature, with a relatively small number of core journals receiving the largest number of citations. For chemical technology the majority of cited journals were classified as very basic science, suggesting a short distance between laboratory and industrial applications in chemical technology. In the electrical/electronics patents the cited literature was relatively more applied, indicating a somewhat larger distance between basic research and industrial application in the electrical/electronics field, at least for the Netherlands. This is, of course, completely consistent with the data already presented in this paper, based on all U.S. patents in the 1975-1980 time-frame. They also made the important observation that patents invented in English speaking countries seem to contain more scientific references than patents from non-English speaking countries, and suggest a hypothesis that the availability of information pertaining to patents may depend, at least for the U.S. patent system, on the language in which the science is communicated (English or not) and, thus, there may be some language bias in the U.S. patent-to-science linkage data.
3. Magnitude
of the linkage
The work reported here is based on the 1989 concordance which differs from our earlier work on the 1975-1980 patents mainly in that for the 1989 concordance patents are fractionated, rather than double counted. That is, if a patent is mapped by the concordance into the product fields of drugs and medicine, and also into one of
the product fields of chemistry such as organic chemistry, then the patent is split one-half to drugs and medicine, and one-half to organic chemistry, and any “Other references” cited are similarly split half to drugs and medicine, and half to organic chemistry. While this procedure eliminates double counting, it does still have some difficulty, especially related to drugs and medicine and chemistry, and at least in interpretation in professional and scientific instruments. There are two sources for the drugs and medicine and chemistry problem, one an ambiguity in the organic area itself, and another an artifact of the U.S. Patent Office system which has specific classes for drugs, bioaffecting. In these classes, pesticides, which are bioaffecting, are included, as well as human and veterinary medicines, The main result of this is that large numbers of agricultural chemical patents are split by the concordance at least partially into drugs
and medicine. Similarly, there are many organic chemical classes based upon chemical structure which are biologically active, and differentiating between those that are biologically active in the insecticidal sense, and those that are biologically active as medicines is extremely difficult. At times it is impossible because in one dose a certain chemical may be a pesticide, and in another dose it may be a medicine. One result of this is that there is a stronger dependence of the chemical industry upon biomedical research shown by this data than is actually the case, simply because of the partial attribution of references from drug and medicine patents to the chemical industry. Possibly also misleading, perhaps more of an obfuscation, is the multiple classification which occurs in the professional and scientific instruments product field. This field contains a rather broad range of instruments, including many from medicine, and others from physics. To add to the confusion, the instruments from physics may have
F. Narin and D. Olicastro / Linkage between technology and science
With that background the most striking new results to be reported here is the increase in magnitude of the number of “Other references” cited on U.S. patents, which has been increasingly steadily from 1975 through 1989, with no slowing down whatsoever. This increase in magnitude is occurring virtually across the board, in almost every product field, and in almost every country. Furthermore, the general pattern of national difference is retained. The U.S. has the largest number and the most rapid rate of increase across almost all of the product fields, the Japanese have the smallest number and the smallest rate of increase, and the three major European countries, the United Kingdom, France and Federal Republic of Germany are intermediate between these two extremes, with the U.K. and its strong emphasis in pharmaceutical patenting closer to the U.S. pattern than the other two European countries. This can be seen most clearly in fig. 1, which shows the national pattern of science linkage for all product fields combined, and in fig. 2, which
either an industrial or a medical application, an example being lasers. Some of the medical devices are known to include surgical drapes and bandages, which are not always thought of as instruments. All of this need not obscure the data, since the result is a fairly accurate representation of what is going on in the product field, namely, a linkage from professional and scientific instruments to several different areas of science. One must only keep in mind that large numbers of patents related to medical applications and devices are included in this product field. In on-going work at CHI on our TECH-LINE”” database, modifications have been made to the concordance to resolve some of these ambiguities, including a partitioning of professional and scientific instruments into three parts - applicable to drugs and medicine, chemistry and the electrical industry - and a reclassifying of some of the pesticide and organic chemical patents. However, data will not be available from TECHLINE”” for some months, and would not, in fact, change the fundamental conclusions of this paper. 8.00 7.00 T y 6.00 a"
/US
(4
I
0.00~ 1975
:
:
:
:
:
:
:
:
:
:
:
:
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
19M
:
1989
1985
1986
1987
1988
1989
1
Year
197S
1976
1977
1978
1979
1980
1981
1982
1983
1984
Year
Fig. 2. Linkage
to science
in (a) drugs and medicine,
243
and (b) electrical
machinery
(both smoothed).
shows the same data for two specific product fields, drugs and medicine - the most science linked of all of the product fields - and electrical machinery, one of the least science tinked of the fields. The rather clear differentiation of Japan as a low science linked country shown in fig. 1 is not as apparent in fig. 2 and, in fact, is not quite as apparent in specific fields. In general, Japanese inventors tend to be slightly below European inventors in their science linkage in most of the product fields, but there is not a major difference, and it is certainly of marginal significance. The very low overall pattern of Japanese linkage is mainly due to their relatively low emphasis on drugs and medicine and chemical patents, both of which are science linked areas, and their heavy emphasis on electronics which is not, in general, as strongly linked to science, although when linked to science, electronics links to very recent science. Note that fig. I and 2 arc. based on assigned patents only. Patents that are owned by an individuat inventor and not assigned to a company are not counted. In the I.J.S. patent system approximately 25% of the U.S.-invented patents are unassigned, that is, they are owned by the individual inventor, and tend not to be industrially important patents. For inventors from most other countries 5-10% of the patents are individually owned and not assigned to companies. These tend also to be consumer products patents, or mechanically oriented - modification of a surgical instrument patented by an individual physician - and not the kind of patent which would characterize national industrial strength. AS would be expected, of course, there are very few Japanese inventors patenting individually in the U.S., only one to two percent of the Japanese-invented patents, reflecting undoubtedly both the expense to the individual of translating and reworking a patent from Japanese to English, but also the cooperative and corporate mode of invention in the Japanese system.
4. Nature of the linkage This section will discuss some preliminary data on the nature of linkage between U.S. patents and scientific research literature. It is based fargeiy on some research performed for the B&&T in Germany in cooperation with Fraun-
hofer ISI in Karlsruhe 181, and data currently being deveioped in a project sponsored mainly by the CNRS in France (93. In future reports, as mentioned earlier, the overlap of patent classification will be clarified. However, the results are important enough and strong enough that those clarifications will be ones of flavor rather than substance, and we feel it is more important to present the status of the data as is today, rather than wait a year or more for that refinement. This section will be based on U.S. patents issued between 1987 and 1988. For those two years CHI has done a complete unification of ail of the “Other references” cited on the front pages of U.S. patents, By complete unification we mean that each reference has been individually scanned and assigned to specific categories. We have used a six-part classification for the references:
such as Scier-rcc or h’ature; (2) non-SC1 covered journal, such as L3ulletitzof
National (3) (4) (5) (6)
Institute
of Agricultrtral
(Tokyo); chemical abstract; non-chemical abstract, physics abstract; book; all other documents.
such
Science
as a biology
or
The other documents are often product specifications, company reports, technical disclosures, and generally are nonscientific in nature. Chemical Abstracts referred to in the U.S. patent system are quite often non-English sources, such as Japanese patents which are often referred to by the patent examiner through their Chemical Ab~fract.~ rather than directly. The other abstracts, which tend to be Physics Abstracts, BioEogicaE Abstracts, and so forth, are generally scientific in nature. Fig. 3 shows graphically the number of other publications cited per patent for all “Other references” cited and for Science CittrGctn ~M&ZZiSCI) covered journals, for each of the seven major SIC categories which will be used for the rest of this paper. The figure is sorted in order of total number of “Other references” cited and shows, of course, that drugs and medicine is the field most heavily
245
F. Narin and D. Olivastro / Linkage between technology and science
Chemicals
Prof & Sci Instr
Transporta 1
0
1
a.5
1.5
2
215
3
# of Other References per Patent Fig. 3. Linkage
to science
by product
fields, and type of reference.
Fig. 4. Cited fields and citing countries
for drugs and medicine
3.5
4
4.5
24ti Table 3 Science citation Citing country
per patent No. Pats
by product
field. country,
873 902 2837 3 100
U.S.
Ix?X
Other World
2.157 232X6
(7) Dru,q~ utul rnrdrcirw France 146 U.K. 2o.i FRCi 2X6 Japan SO.3 U.S. 1717 Other 41X World 3274
CM&BR
0.57 0.65 0.40
0.46 0.07 0.71 0.77
I.61 1.7’)
I ,A5 1.70 4.35 2.63 3.lY
(3) Corrq~~rrrtr,qrued c,otnr?rltrzi~trriorls France X34 0.35 U.K. 7x7 0.36 FRG IS23 0.27 Japan X55X 0. I6 U.S. IISXS 0.44 Other 1772 0.1’) 2505’) World 0.3 I (3) ~~ir,is/,o,.tcrlio,I France U.K. FRG Japan
307 272 I Oh!, 2 IO!,
U.S.
1.338
0.00 0.03
Other World
SYO 6770
0.0 I O.OI
0.01 0.00 0.01
(S ) t’~of;~.~.sio~~cil rrul ,scicwt~fic~ itl.~trmwnt~~ France S4S 0.47 lJ.K. hXh 0.4X FRG 142X 0.33 522’) 0. IY Japan U.S. X5X4 0.81 Other 1544 0.43 IXOIX 0s Wol-Id illuchirwr~ (e.rchrdin,~ c.ornprtit~ji ut7tl col,in7lrtlr~rrtio,la! France 131 0.10 0.01 U.K. 1723 0. IS 0.03 FRG 4507 0.08 0.01 Japan 7020 O.Oh 0.01 U.S. IS477 0.17 0.03 Othet 44lY O.Oh 0.01 War-Id 33900 0.17 0.02 (6)
field
Cited field All
France U.K. FR
and cited scientific
Chem
Physics
En & Tech
-
Other
F. Narin and D. Olic~astro / Linkage
betweetz technology
247
and science
Table 3 (continued) Citing country
No. Pats
Cited field All
CM&BR
Chem
Physics
En &
Tech
Other
(7) Other France
886
0.08
0.01
0.03
0.01
U.K.
725
0.07
0.01
0.01
0.02
0.02 0.03
o.tW 0.01
FRG
1980
0.07
0.00
0.01
0.02
0.03
0.00
Japan U.S. Other
3957 11323 2520
0.09 0.16 0.08
0.00 0.03 0.02
0.01 0.03 0.02
0.05 0.03 0.01
0.03 0.05 0.02
0.00 0.02 0.02
World
21390
0.12
0.02
0.02
0.03
0.04
0.02
4842 4799 13620 31565 63252 13619 131697
0.31 0.38 0.23 0.19 0.57 0.31 0.40
0.09 0.13 0.06 0.05 0.25 0.14 0.16
0.08 0.09 0.08 0.04 0.12 0.09 0.09
0.06 0.07 0.05 0.05 0.0’) 0.04 0.07
(1.07 0.07 0.04 0.04 0.09 0.04 0.06
0.01 0.01 0.00 0.01 0.02 0.01 0.0 1
(8) All patents France U.K. FRG Japan U.S. Other World
linking to science; next comes chemistry and chemical products, followed by professional and scientific instruments, computing and communications, and then at a much lower level machinery, transportation and other. It is also interesting to note that the more heavily linked fields have the larger fraction of “Other references” which are to the scientific literature. Overall, in drugs and medicine, 72% of the “Other references” cited are to SC1 journals and another 5% to other journals. In chemical and chemical products these fractions are down, but still more than 60% are to scientific journal materials. In professional and scientific instruments the ratio is approximately the same, but in computing and communications it is slightly less than 50%, and in transportation, machinery and others the majority of “Other references” cited are not scientific journals, but are, in fact, to the category “Other”, which is largely technical reports, specifications, disclosures, and so forth. There is almost a double effect: the product fields with large numbers of “Other references’ also have larger fractions of those references going to scientific research papers and so are, in fact, even more heavily science linked, relative to the other product fields, than is indicated just by the tabulation of the number of “Other references” cited on the front pages. The last set of data to be shown here will illustrate the nature of the linkage, that is, the fields of science which are cited by the SC1 refer-
ences in the patents, for the major product field categories. The data themselves are summarized in table 3, which shows the number of references to SC1 journal papers per patent by cited field for the seven major SC1 categories and for all categories combined. The cited fields are obviously radically different, and obviously in accord with one’s expectations. This is clearly seen in the contrast shown in fig. 4 and 5. Fig. 4 shows the fields of the SCZ papers cited by drugs and medicine for which the references are clearly very heavily concentrated in clinical medicine (CM) and in biomedical research (BR), with a somewhat lower rate of citing to chemistry. Some of the citing to chemistry is as mentioned previously - an artifact of the fact that in this classification scheme the pesticide patents, which are basically agricultural chemicals, but are biologically active, are split between drugs and medicine and chemistry. A clear contrast to fig. 4 is shown by fig. 5, which is similar data for the fields of computing and communication. In this figure virtually all of the significant citing is to engineering and technology, and to physics, in sharp contrast with drugs and medicine. Note here, however, that some of the national differences are still apparent: even in computing and communications, a field in which the Japanese excel, their patents tend to link up to scientific research papers rather considerably less
248
Fig. 5. Cited fields and citing countries
for computing
and communications.
than the patents with inventors from the U.S., the U.K. and France, and somewhat less than for Germany. In professional and scientific instruments a similar plot shows, in fact, the broad scope of the cited field, with the largest number of “Other references” cited to physics, the next largest to the medical fields, the third largest to engineering and technology, and then the least to chemistry. This reflects the large amount of instrumentation which is industrial in nature, but also a significant amount of medical instrumentation, medical devices and applications and, of course, the dependence of those devices upon research which is in the physics and electrical engineering journals.
5. Discussion The conclusions that reviewing this data are
may be arrived at by reasonably straightfor-
ward, and certainly in accord with one’s intuitive expectation, and the perception of Price and Toynbee and others decades ago: science and technology are inextricably linked. The most important conclusion from the data amassed so far is that the embrace of the dancers is getting stronger, and the tempo of the music is getting quicker, and the relationship is almost one in which there is barely a distinction left. The title of one of our papers was “Is Technology Becoming Science?” The answer is that, if it is not becoming science, it is certainly becoming very close to science, especially in the areas of hightech growth such as drugs and medicine, chemicals, and computing and communications. The areas which are leading the industrial growth of the West are just those areas that are very science intensive, and it is hard to imagine sustained industrial growth in any country without a strong competence in the scientific fields which so closely underlie these modern technologies.
F. Narin and D. Olilastro
/ Linkage between technology and science
It is also interesting to note that an argument can also be made here for the need to sustain a broad scientific capability. Although it is quite clear that different technologies depend heavily on rather industry-specific areas of knowledge, the boundaries between scientific fields are not clear, and a major technology such as professional and scientific instrumentation is drawing upon the resources of physicists, chemists, engineers and physicians, and all other parts of the basic research spectrum in developing and protecting its inventions. As a final point, in research which is still underway at CHI there is evidence suggesting the existence of a significant national component in science linkage. That is, there is some tendency for German-invented patents to cite German originated science, and for U.S.-invented patents to cite U.S. science, just as there is in the scientific literature a certain national component, and over-citing of each country’s scientific research by other researchers in the country. Certainly in science this is a completely natural phenomenon, reflecting the close developmental relationship between current research in a country, and earlier research in the country, which in science is often simply a reflection of the coherence of the streams of research within an individual university or research group. We expect to show in future papers that this local flow of research knowledge, which is so clear in basic science, also exists to a significant degree in the flow of national science into technology and, thus, in the future, to further delineate this rich and active relationship between these two facets of technical growth.
References [II M.P. Carpenter,
Patent citation as indicators of scientific and technological linkages, AAAS Annual Meeting, (Detroit, MI, USA, May 30 1983).
PI M.P. Carpenter
249
and F. Narin. Validation study: Patent citations as indicators of science and foreign dependence, World Patent information, 5 (3), (1983) 180-185. M. Cooper and F. Narin, Linkage he[31 M.P. Carpenter, tween basic research literature and patents, Research Management, 23 (2) (March, 1980) 30-35. [41 P. Collins and S. Wyatt, Citations in patents to the basic research literature, Research Policy, 17 (1988) 65-74. historically indepen[51 D.J. de Solla Price. Is technology dent of science? A study in statistical historiography. Technology Culture, 6 (1966) 553-56X. [61 F. Narin and E. Noma, Is technology becoming science’?, Scientometrics, 7 (3-6) (1985) 369-381. Patent citation [71 F. Narin, M. Rosen and D. Olivastro, analysis: New validation studies and linkage statistics, in: A.F.J. van Raan, A.J. Nederhof and H.F. Moed (eds.), Science Indicators: Their Use in Sclencr Policy and Their Role in Science Studies (DSWO Press, The Netherlands, November 1988). [81 D. Olivastro and F. Narin. Definition of Fields in Close Cooperation between Science and Technology (Bundesministerium fuer Forschung und Technologie, Bonn, Germany, August, 1989). [91 D. Olivastro and F. Narin, The Technological Utilization of European Science, First Interim Report (Centre National de la Recherche, Paris, France, October 1990). for journal 1101 G. Pinski and F. Narin, Citation influence aggregates of scientific publications: Theory, with application to the literature of physics. Information Processmg and Management, 12 (5), (1976) 297-312. illI Rer?ew and Assessment of the OTAF Concordunce between the U.S. Patent Classification and the Standard Industrial Classification Systems: Fmal Report, Office of Technology Assessment and Forecast, Patent and Trademark Office, (U.S. Department of Commerce, January 1985). and L.E. Birdzell Jr., Science, technology [121 N. Rosenberg and the western miracle, Scientific American, 263 (5) (November, 1990) 42-54. [I31 A.J. Toynhee. A Study of Hi.ytory (Oxford University Press, UK. 1962). [14] B.C. Van Vianen, H.F. Moed and A.F.J. Van Raan, An exploration of the science base of recent technology, Science Policy, 19 (1990) 61-81.
Status report: Linkage between technology and science Francis
Narin
and
Dominic
Olivastro
CHI Research Inc., 10 White Horse Pike, Haddon Heights NJ 08035, USA Final version
received
May 199 1
A status report is presented on indicators of the linkage between technology, as characterized by granted U.S. patents, and science as characterized by the “Other references” cited on the front page of those patents. It is shown that these other references have increased threefold in recent years from fewer than one-third per patent in 1975 to more than one per patent in 1989. These science linkages occur most heavily in pharmaceutical, chemical and electronics patents; the cited science is youngest in electronics and pharmaceuticals with a median age of three to four years, similar to the age of research papers cited in other research papers. The cited science varies significantly for patents in the different major countries, at least partially reflecting the national differences in technological emphasis, including the strong electronic emphasis for Japanese patenting, and the U.S. and U.K. strengths in pharmaceuticals.
1. Introduction It has long been perceived that there is a continuum stretching from very basic scientific research, through applied research and technology, to economic growth and national prosperity. In his 1965 paper entitled “Is Technology Historically Independent of Science? A Study in Historiography” [5] the late Derek de Solla Price quoted Toynbee’s description that “physical science and industrialism may be conceived of as a pair of dancers, both of whom know their steps, and have an ear for the rhythm of the music. If the partner who has been leading chooses to change parts and to follow instead, there is perhaps no reason to expect that he will dance less correctly than before” [ 131.
Thus the close linkage and feedback between the scientific, industrial and technological communities has been long recognized. Moreover, the key role that this linkage has played in the development of the economies of the West has been clearly called out by Rosenberg and Birdzell who, in a recent article “Science, Technology, and the Western Miracle” point out that “close links between the growth of scientific knowledge and the rise of technology have permitted the market economies of the western nations to achieve unprecedented prosperity” [ 121. Yet, with all of this qualitative understanding of linkage, there has been very little quantitative data to specifically characterize this relationship, or to pinpoint the subject, national and temporal aspects of the coupling between technology and science. Fortunately, the “Other references” cited in U.S. patents provide a means for directly measuring this link. This paper presents and updates data from a series of studies that CHI Research, Inc. (CHI) has been carrying out over the last ten years, to directly measure the relationship between technology and science. All of these studies have centered around use of the references in U.S. patents, especially the front page or examiner “Other references” cited. CHI’s studies have both counted and characterized these references, and used them to establish the links between the technology embodied in the patent, and the scientific research upon which it is dependent.
2. Earlier studies The first of these studies, “Linkage between Basic Research Literature and Patents”, looked
Research Policy 21 (1992) 237-249 North-Holland 0048-7333/92/$05.00
0 1992
Elsevier
Science
Publishers
B.V. All rights reserved
F. Narirl und D. Olil,astro / Lmkuge
23x
at the referencing in the mid-1970s in two of the most rapidly growing areas of U.S. patenting, gas lasers and prostaglandins [3]. Gas lasers were selected because of their growing application in many areas of technology, and prostaglandins because of their very significant medical potential. It was found that the patents in those two very scientific areas of technology contain many citations to the scientific literature, 10 per patent for prostaglandins and two to three per patent for gas lasers. Further, it was shown that close to 90% of all of the journal references are to either basic or applied scientific journals, as opposed to engineering journals or to the technological literature. It was also found that the time between the publication of a journal article and the patent citing that article was relatively short, generally three to five years, which is quite similar to the amount of time that elapses between the publication of a scientific article and its citation by other scientific articles. It was concluded that this evidence “clearly indicates that the process of reduction to practice in the industrial community continues to require recent science, and the sup-
Table I Citations
to science
from U.S. patents, Number patents ”
Other references per patent
Journal ref per patent
1 2 3 15 16 17 1X 21 22 33 44 55 56
4750 4277 72857 5348 20768 963 1 5253 46191 114071 74153 26813 49880 30743
0.62 0.26 0.68 0.15 0.13 0.13 0.21 0.06 0.07 0.22 0.03 0.23 0.06
3X3292
All ’ Product
nnd .scirnce
port of such science is a necessary prerequisite for the continuing emergence of new technology.” Three subsequent CHI documents expanded upon and generalized that first finding of strong linkage between technology and science. In the first of these, a validation study of patent citations as indicators of both science and foreign dependence, we formally tested whether the number of front page, examiner citations per patent to the scientific literature corresponded to peer rankings of the science dependence of the technologies [2]. A total of 24 technologies were chosen for this, 12 of which were judged in advance to be science-dependent and 12 judged in advance to be foreign-dependent. A peer group of 19 high level R&D managers was asked to rank these technologies in terms of both their science and foreign dependence. The bibliometric rankings were then compared with the peer ranks. A high degree of agreement was found between the expert opinions and the corresponding bibliometric rankings. For example, the eight technologies judged most science-dependent by experts averaged 0.92 examiner citations per
197551980
Major product group
Food Kind. Prod. Textile Mill Pro Chem. Allied Pro Petroleum Nat. Rubber & Misc. Stone, Clay, Gl Primary Metals Fab. Metal Prod Mach., Expt. El Electr. & Elect Transporta. Eq. Profess. 6t Scie Unclassified
hetwrerz technology
Number
of references
to
Average level
Applied technology
Engineering science
Applied research
Basic research
0.28 0.1 1 0.31 0.07 0.05 0.05 0.09 0.03 0.03 0.12 0.01 0.15 0.02
(LVI) 70 202 780 95 160 SO 80 151 789 1489 6X 876 283
(LV2) 200 81 1586 59 243 162 107 21s 722 2437 44 1288 78
(LV3) 315 61 5077 48 413 129 110 407 458 2732 13 2801 77
(LV4l 627 44 13740 49 82 39 52 91 250 638 19 1260 63
3.2 1.9 3.5 2.2 2.5 2.4 2.4 2.5 2.1 2.4 1.9 2.7 1.8
0.23
0.11
4326
6256
11017
15754
3
I.7734 11857
1.OJ 1.01
0.5 0.42
175 132
538 373
2007 1304
3646 279X
3.4 3.5
31654
0.78
0.39
287
467
I977
X923
3.7
subgroups
Drugs, medicines Agricultural chemicals Industrial Organic Chemicals
’ Some patents are classified into more than one product h The “All” line counts the references from these patents
group only once
F. Narin and D. Olic~astro / Linkage between technology and science
patent to scientific journal literature, while the eight technologies judged least science-dependent had only 0.05 citations per patent to journal papers. These findings thus provided support for the hypothesis that the technology-to-science linkage was much broader than just for the two technologies studied in CHI’s first paper. The magnitude and direction of this linkage was further developed and reported in a paper presented at the American Association for the Advancement of Science meeting in May of 1983 [I]. That data is summarized in table 1. The classification is based on the U.S. patent office’s initial concordance between patent classification and Product Fields based on the U.S. Standard Industrial Classification (SIC) ill]. The citations were obtained from the unification of all of the references from the front page of essentially all U.S. patents issued between 1975 and 1980. The number of these citations to technical and scientific literature was tabulated. The number of these references per patent is relatively modest, 0.23; the literature references are approximately half, 0.11 per patent to journals. However, in such specific product fields as drugs and medicine, agricultural chemistry and industrial organic
Table 2 Citations
to six major fields of science,
Number other refs ”
1 2 3 15 I6 17 18 21 22 33 44 55 56
1202 388 21023 248 893 376 348 850 2184 7185 134 6159 496
All h Product subgroups Drugs. medicines Agricultural chemicals Industrial organic chemicals
Food Kind. Prod. Textile Mill Pro Chem. Allied Pro Petroleum Nat. Rubber & misc. Stone. Clay, Gl Primary Metals Fab. Metal Prod Mach., Expt. El Electr. & Elect Transporta. Eq. Profess. & Scie Unclassified
chemistry the figures are rather considerably higher, and they are of course, very low in transportation equipment, and other mechanically, rather than scientifically, related fields. A further interesting observation is that many of the journal references are to relatively basic journals. On CHI’s research level scale the most basic journals are in Basic Research (Level 41, followed by Applied Research (Level 3), Engineering Science (Levels 2), and Applied Technology (Level l)[lO]. Table 1 also shows the level distribution of papers cited from each of those product groups. It is clear that for most of the fields the average level is weighted toward applied research, with only one third or fewer papers in applied technology and engineering science. In particular, patents in chemistry and allied products, which include drugs and medicines, heavily cite basic research journals. The scientific papers cited on the front pages of U.S. patents are published largely in basic and applied research journals. The fields of science cited by these 1975 to 1980 patents, summarized in table 2, are also interesting and revealing. The major contrasts are between electrical and electronics, for which the
1975-1980
group
Major product
239
Percent
of these references
to
Clinical medicine
Biomedical research
Biology
Chemistry
Physics
Engineering
16 19 0 3 1 1 3 4 3 1 24 10
36 1 12 2 1 2 1 2 5 5 1 15 4
29 0 3 0 0 1 0 1 4 0 1 1 2
14 24 59 36 28 24 14 22 12 8 9 15 17
0 4 1 3 28 19 24 33 13 35 7 29 7
4 70 6 59 52 53 62 38 62 49 80 I6 60
36972
14
9
3
39
13
21
6322 4574 11602
39 31 11
18 I7 7
4 8 2
39 43 74
0 0
1 1 5
I
” Some patents are classified into more than one product group h The All line counts the references from these patents only once
I
240
F. Narin and Il. Olimstro
/ Linkage hetweerz technology and .scicwce
great majority of references, approximately 75% are to physics and engineering journals, and chemistry and allied products with only 7% of the science references to physics and engineering. Appropriately, food and kindred products cites to the biological literature more heavily than any other product group, and also cites to biomedicine and chemistry. Chemical and allied products cites, of course, largely to chemistry, but also to clinical medicine and biomedical research, but that is partially due to the fact that the drug and medicine classes are included, in the upper part of the table, in the chemical and allied product major product groups. An interesting balance is shown by professional and scientific instruments, which cites quite heavily both to clinical medicine and biomedical research, and also to physics and engineering. If one looks at the patents that are contained in this product group, they span the whole area of instrumentation from medical instrumentation to lasers for physics and enginecring applications, and the science cited by these product groups shows its dependence and linkage to those two major classes of application, biomedical and industrial. The more precise product subgroups shown at the bottom part of the table further show these trends, with drugs and medicine giving almost 60% of its references to clinical medical and biomedical research, and most of the rest to chemistry, while industrial organic chemistry has 75% of its references to chemistry. Agricultural chemicals, which includes many biologically active compounds which are cross classified into drugs and medicine, is much more evenly split in its science dependence on both chemistry and the biomedical fields. In fact, the subjectively appropriate nature of these linkages is a kind of dual validation: it both shows that the kind of science that one knows is relevant to those technologies is cited by them, and it also indicates that the concordance created by the patent office has, in fact, quite well categorized the patents into technologies that have similar scientific and engineering dependencies. A further step in understanding the relationship between technology and science was embodied in a subsequent paper, “Is Technology Bein which citation and referenccoming Science?“, ing data from recent biotechnology patents and biosciences papers were analyzed. [6] Specifically,
in that paper it was shown that the time distribution of references from both patents and papers are similar, with a peak in the citation distribution at two to four years prior to the publication of the paper or issue of the patent. This two to four year lag was essentially the same for patents citing patents, for papers citing papers, and for patents citing papers. From that we concluded that science and technology are very closely linked, and that, in fact, the division between leading edge biotechnology and modern science has almost completely disappeared. This corresponds in a very quantitative way to the observation, in our first linkage paper, that reading the prostaglandin patent was very similar to reading a scientific paper. The arrangement of the materials was slightly different, but the content was virtually identical. A patent in that highly science-dependent area was virtually identical in substance to a scientific paper in the same area, and had the same referencing and other characteristics. One additional set of data has recently been published summarizing some of the overall trends in science linkage, namely the aggregate trend in number of “Other references” cited on the front pages of U.S. patents from 1975 to 1985, and the trends in the median age of these references. [71 In that paper it was shown that the number of these other references had increased from approximately 0.2 per U.S. patent in 1975 to between 0.3 and 0.8, depending on the country, ten years later. The median age of those references has decreased dramatically, by one to two years, for most of the major countries studied, with the median age of references cited in U.S.-invented U.S. patents only 6.5 years, and Japanese-invented patents less than 7 years. That data, however, looked at all of the patents of five major technological powers, the U.S., Japan, West Germany, France, and the United Kingdom in the aggregate, and did not account for the significant differences in patent emphasis of the countries. The differences seen between the countries, with Japanese-invented U.S. patents having the smallest science-dependence and the U.S. the largest, are at least partially due to the relatively heavy U.S. emphasis on pharmaceuticals, a particularly science-dependent area, as opposed to the Japanese emphasis on electronics, a moderately science-dependent area. Similarly, the relatively
F. Narin and D. Olirastro / Linkage between technology and science
old median age of the references in the German invented patents, some one to two years older than the average reference cited in a Japanese or a U.S. invented patent, is almost certainly due to the very heavy emphasis of German technology on traditional areas of mechanical and chemical technology. The data presented in the next section of this paper will separate out these effects of product field emphasis and national emphasis. Two additional recent studies of linkage should be mentioned, as they provided further data about the linkage between technology and research. Collins and Wyatt [4] reported on citations in patents to the basic research literature, focusing on the linkage between genetics technology, as contained in 366 genetics patents issued in the U.S. system in the early 1980s and the research cited both by the examiners and by the applicants in those patents. They extracted both the examiner references from the front pages, and the applicant references in the text of the patents, unified them, traced them to the underlying scientific papers, and looked at characteristics of the linkage. Amongst their key observations were that the peak of citations was to very young papers, aged two to three years, corresponding, as has been seen in other data, to a time lag between technology and science which is no longer than the time lag between scientific papers and successor papers. They also found that the general characteristics of the citations from both examiner and applicant were quite similar; in both cases 80% or so of the citations were to very basic, Level 4 research journals. Finally, they found that there were perceptible differences in the country to country linkages, with a clear tendency for a given country’s patents to cite research papers from the same country. However, over and above this, the citation performance of U.K. papers in genetics was found to be very strong, with a disproportionate U.K. representation in the highly cited papers, and almost 12% of all of the science cited in genetics technology originating in the U.K. The U.K.‘s performance in genetics research, as indicated by these citations was characterized as “in both absolute and relative terms . . . the U.K. produces significantly more papers that are useful to patenters than FRG, France or Japan” (p. 72).
241
In another study of the science base of recent technology Van Vianen et al. [14] at the University of Leiden used the references in U.S. patents to identify the science base of recent technological developments. They studied two data sets, all 1985 U.S. patents in the field of chemical techand pharmaceuticals, and all nology Netherlands-invented U.S. patents for all fields of technology for the period 1982-1985. They found that the field of pharmaceuticals uses relatively young science, whereas the chemical technology subfield of organic compounds uses relatively old science. They also found that the journals cited in patent references show a remarkable parallel with the distribution of journals cited in the serial literature, with a relatively small number of core journals receiving the largest number of citations. For chemical technology the majority of cited journals were classified as very basic science, suggesting a short distance between laboratory and industrial applications in chemical technology. In the electrical/electronics patents the cited literature was relatively more applied, indicating a somewhat larger distance between basic research and industrial application in the electrical/electronics field, at least for the Netherlands. This is, of course, completely consistent with the data already presented in this paper, based on all U.S. patents in the 1975-1980 time-frame. They also made the important observation that patents invented in English speaking countries seem to contain more scientific references than patents from non-English speaking countries, and suggest a hypothesis that the availability of information pertaining to patents may depend, at least for the U.S. patent system, on the language in which the science is communicated (English or not) and, thus, there may be some language bias in the U.S. patent-to-science linkage data.
3. Magnitude
of the linkage
The work reported here is based on the 1989 concordance which differs from our earlier work on the 1975-1980 patents mainly in that for the 1989 concordance patents are fractionated, rather than double counted. That is, if a patent is mapped by the concordance into the product fields of drugs and medicine, and also into one of
the product fields of chemistry such as organic chemistry, then the patent is split one-half to drugs and medicine, and one-half to organic chemistry, and any “Other references” cited are similarly split half to drugs and medicine, and half to organic chemistry. While this procedure eliminates double counting, it does still have some difficulty, especially related to drugs and medicine and chemistry, and at least in interpretation in professional and scientific instruments. There are two sources for the drugs and medicine and chemistry problem, one an ambiguity in the organic area itself, and another an artifact of the U.S. Patent Office system which has specific classes for drugs, bioaffecting. In these classes, pesticides, which are bioaffecting, are included, as well as human and veterinary medicines, The main result of this is that large numbers of agricultural chemical patents are split by the concordance at least partially into drugs
and medicine. Similarly, there are many organic chemical classes based upon chemical structure which are biologically active, and differentiating between those that are biologically active in the insecticidal sense, and those that are biologically active as medicines is extremely difficult. At times it is impossible because in one dose a certain chemical may be a pesticide, and in another dose it may be a medicine. One result of this is that there is a stronger dependence of the chemical industry upon biomedical research shown by this data than is actually the case, simply because of the partial attribution of references from drug and medicine patents to the chemical industry. Possibly also misleading, perhaps more of an obfuscation, is the multiple classification which occurs in the professional and scientific instruments product field. This field contains a rather broad range of instruments, including many from medicine, and others from physics. To add to the confusion, the instruments from physics may have
F. Narin and D. Olicastro / Linkage between technology and science
With that background the most striking new results to be reported here is the increase in magnitude of the number of “Other references” cited on U.S. patents, which has been increasingly steadily from 1975 through 1989, with no slowing down whatsoever. This increase in magnitude is occurring virtually across the board, in almost every product field, and in almost every country. Furthermore, the general pattern of national difference is retained. The U.S. has the largest number and the most rapid rate of increase across almost all of the product fields, the Japanese have the smallest number and the smallest rate of increase, and the three major European countries, the United Kingdom, France and Federal Republic of Germany are intermediate between these two extremes, with the U.K. and its strong emphasis in pharmaceutical patenting closer to the U.S. pattern than the other two European countries. This can be seen most clearly in fig. 1, which shows the national pattern of science linkage for all product fields combined, and in fig. 2, which
either an industrial or a medical application, an example being lasers. Some of the medical devices are known to include surgical drapes and bandages, which are not always thought of as instruments. All of this need not obscure the data, since the result is a fairly accurate representation of what is going on in the product field, namely, a linkage from professional and scientific instruments to several different areas of science. One must only keep in mind that large numbers of patents related to medical applications and devices are included in this product field. In on-going work at CHI on our TECH-LINE”” database, modifications have been made to the concordance to resolve some of these ambiguities, including a partitioning of professional and scientific instruments into three parts - applicable to drugs and medicine, chemistry and the electrical industry - and a reclassifying of some of the pesticide and organic chemical patents. However, data will not be available from TECHLINE”” for some months, and would not, in fact, change the fundamental conclusions of this paper. 8.00 7.00 T y 6.00 a"
/US
(4
I
0.00~ 1975
:
:
:
:
:
:
:
:
:
:
:
:
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
19M
:
1989
1985
1986
1987
1988
1989
1
Year
197S
1976
1977
1978
1979
1980
1981
1982
1983
1984
Year
Fig. 2. Linkage
to science
in (a) drugs and medicine,
243
and (b) electrical
machinery
(both smoothed).
shows the same data for two specific product fields, drugs and medicine - the most science linked of all of the product fields - and electrical machinery, one of the least science tinked of the fields. The rather clear differentiation of Japan as a low science linked country shown in fig. 1 is not as apparent in fig. 2 and, in fact, is not quite as apparent in specific fields. In general, Japanese inventors tend to be slightly below European inventors in their science linkage in most of the product fields, but there is not a major difference, and it is certainly of marginal significance. The very low overall pattern of Japanese linkage is mainly due to their relatively low emphasis on drugs and medicine and chemical patents, both of which are science linked areas, and their heavy emphasis on electronics which is not, in general, as strongly linked to science, although when linked to science, electronics links to very recent science. Note that fig. I and 2 arc. based on assigned patents only. Patents that are owned by an individuat inventor and not assigned to a company are not counted. In the I.J.S. patent system approximately 25% of the U.S.-invented patents are unassigned, that is, they are owned by the individual inventor, and tend not to be industrially important patents. For inventors from most other countries 5-10% of the patents are individually owned and not assigned to companies. These tend also to be consumer products patents, or mechanically oriented - modification of a surgical instrument patented by an individual physician - and not the kind of patent which would characterize national industrial strength. AS would be expected, of course, there are very few Japanese inventors patenting individually in the U.S., only one to two percent of the Japanese-invented patents, reflecting undoubtedly both the expense to the individual of translating and reworking a patent from Japanese to English, but also the cooperative and corporate mode of invention in the Japanese system.
4. Nature of the linkage This section will discuss some preliminary data on the nature of linkage between U.S. patents and scientific research literature. It is based fargeiy on some research performed for the B&&T in Germany in cooperation with Fraun-
hofer ISI in Karlsruhe 181, and data currently being deveioped in a project sponsored mainly by the CNRS in France (93. In future reports, as mentioned earlier, the overlap of patent classification will be clarified. However, the results are important enough and strong enough that those clarifications will be ones of flavor rather than substance, and we feel it is more important to present the status of the data as is today, rather than wait a year or more for that refinement. This section will be based on U.S. patents issued between 1987 and 1988. For those two years CHI has done a complete unification of ail of the “Other references” cited on the front pages of U.S. patents, By complete unification we mean that each reference has been individually scanned and assigned to specific categories. We have used a six-part classification for the references:
such as Scier-rcc or h’ature; (2) non-SC1 covered journal, such as L3ulletitzof
National (3) (4) (5) (6)
Institute
of Agricultrtral
(Tokyo); chemical abstract; non-chemical abstract, physics abstract; book; all other documents.
such
Science
as a biology
or
The other documents are often product specifications, company reports, technical disclosures, and generally are nonscientific in nature. Chemical Abstracts referred to in the U.S. patent system are quite often non-English sources, such as Japanese patents which are often referred to by the patent examiner through their Chemical Ab~fract.~ rather than directly. The other abstracts, which tend to be Physics Abstracts, BioEogicaE Abstracts, and so forth, are generally scientific in nature. Fig. 3 shows graphically the number of other publications cited per patent for all “Other references” cited and for Science CittrGctn ~M&ZZiSCI) covered journals, for each of the seven major SIC categories which will be used for the rest of this paper. The figure is sorted in order of total number of “Other references” cited and shows, of course, that drugs and medicine is the field most heavily
245
F. Narin and D. Olivastro / Linkage between technology and science
Chemicals
Prof & Sci Instr
Transporta 1
0
1
a.5
1.5
2
215
3
# of Other References per Patent Fig. 3. Linkage
to science
by product
fields, and type of reference.
Fig. 4. Cited fields and citing countries
for drugs and medicine
3.5
4
4.5
24ti Table 3 Science citation Citing country
per patent No. Pats
by product
field. country,
873 902 2837 3 100
U.S.
Ix?X
Other World
2.157 232X6
(7) Dru,q~ utul rnrdrcirw France 146 U.K. 2o.i FRCi 2X6 Japan SO.3 U.S. 1717 Other 41X World 3274
CM&BR
0.57 0.65 0.40
0.46 0.07 0.71 0.77
I.61 1.7’)
I ,A5 1.70 4.35 2.63 3.lY
(3) Corrq~~rrrtr,qrued c,otnr?rltrzi~trriorls France X34 0.35 U.K. 7x7 0.36 FRG IS23 0.27 Japan X55X 0. I6 U.S. IISXS 0.44 Other 1772 0.1’) 2505’) World 0.3 I (3) ~~ir,is/,o,.tcrlio,I France U.K. FRG Japan
307 272 I Oh!, 2 IO!,
U.S.
1.338
0.00 0.03
Other World
SYO 6770
0.0 I O.OI
0.01 0.00 0.01
(S ) t’~of;~.~.sio~~cil rrul ,scicwt~fic~ itl.~trmwnt~~ France S4S 0.47 lJ.K. hXh 0.4X FRG 142X 0.33 522’) 0. IY Japan U.S. X5X4 0.81 Other 1544 0.43 IXOIX 0s Wol-Id illuchirwr~ (e.rchrdin,~ c.ornprtit~ji ut7tl col,in7lrtlr~rrtio,la! France 131 0.10 0.01 U.K. 1723 0. IS 0.03 FRG 4507 0.08 0.01 Japan 7020 O.Oh 0.01 U.S. IS477 0.17 0.03 Othet 44lY O.Oh 0.01 War-Id 33900 0.17 0.02 (6)
field
Cited field All
France U.K. FR
and cited scientific
Chem
Physics
En & Tech
-
Other
F. Narin and D. Olic~astro / Linkage
betweetz technology
247
and science
Table 3 (continued) Citing country
No. Pats
Cited field All
CM&BR
Chem
Physics
En &
Tech
Other
(7) Other France
886
0.08
0.01
0.03
0.01
U.K.
725
0.07
0.01
0.01
0.02
0.02 0.03
o.tW 0.01
FRG
1980
0.07
0.00
0.01
0.02
0.03
0.00
Japan U.S. Other
3957 11323 2520
0.09 0.16 0.08
0.00 0.03 0.02
0.01 0.03 0.02
0.05 0.03 0.01
0.03 0.05 0.02
0.00 0.02 0.02
World
21390
0.12
0.02
0.02
0.03
0.04
0.02
4842 4799 13620 31565 63252 13619 131697
0.31 0.38 0.23 0.19 0.57 0.31 0.40
0.09 0.13 0.06 0.05 0.25 0.14 0.16
0.08 0.09 0.08 0.04 0.12 0.09 0.09
0.06 0.07 0.05 0.05 0.0’) 0.04 0.07
(1.07 0.07 0.04 0.04 0.09 0.04 0.06
0.01 0.01 0.00 0.01 0.02 0.01 0.0 1
(8) All patents France U.K. FRG Japan U.S. Other World
linking to science; next comes chemistry and chemical products, followed by professional and scientific instruments, computing and communications, and then at a much lower level machinery, transportation and other. It is also interesting to note that the more heavily linked fields have the larger fraction of “Other references” which are to the scientific literature. Overall, in drugs and medicine, 72% of the “Other references” cited are to SC1 journals and another 5% to other journals. In chemical and chemical products these fractions are down, but still more than 60% are to scientific journal materials. In professional and scientific instruments the ratio is approximately the same, but in computing and communications it is slightly less than 50%, and in transportation, machinery and others the majority of “Other references” cited are not scientific journals, but are, in fact, to the category “Other”, which is largely technical reports, specifications, disclosures, and so forth. There is almost a double effect: the product fields with large numbers of “Other references’ also have larger fractions of those references going to scientific research papers and so are, in fact, even more heavily science linked, relative to the other product fields, than is indicated just by the tabulation of the number of “Other references” cited on the front pages. The last set of data to be shown here will illustrate the nature of the linkage, that is, the fields of science which are cited by the SC1 refer-
ences in the patents, for the major product field categories. The data themselves are summarized in table 3, which shows the number of references to SC1 journal papers per patent by cited field for the seven major SC1 categories and for all categories combined. The cited fields are obviously radically different, and obviously in accord with one’s expectations. This is clearly seen in the contrast shown in fig. 4 and 5. Fig. 4 shows the fields of the SCZ papers cited by drugs and medicine for which the references are clearly very heavily concentrated in clinical medicine (CM) and in biomedical research (BR), with a somewhat lower rate of citing to chemistry. Some of the citing to chemistry is as mentioned previously - an artifact of the fact that in this classification scheme the pesticide patents, which are basically agricultural chemicals, but are biologically active, are split between drugs and medicine and chemistry. A clear contrast to fig. 4 is shown by fig. 5, which is similar data for the fields of computing and communication. In this figure virtually all of the significant citing is to engineering and technology, and to physics, in sharp contrast with drugs and medicine. Note here, however, that some of the national differences are still apparent: even in computing and communications, a field in which the Japanese excel, their patents tend to link up to scientific research papers rather considerably less
248
Fig. 5. Cited fields and citing countries
for computing
and communications.
than the patents with inventors from the U.S., the U.K. and France, and somewhat less than for Germany. In professional and scientific instruments a similar plot shows, in fact, the broad scope of the cited field, with the largest number of “Other references” cited to physics, the next largest to the medical fields, the third largest to engineering and technology, and then the least to chemistry. This reflects the large amount of instrumentation which is industrial in nature, but also a significant amount of medical instrumentation, medical devices and applications and, of course, the dependence of those devices upon research which is in the physics and electrical engineering journals.
5. Discussion The conclusions that reviewing this data are
may be arrived at by reasonably straightfor-
ward, and certainly in accord with one’s intuitive expectation, and the perception of Price and Toynbee and others decades ago: science and technology are inextricably linked. The most important conclusion from the data amassed so far is that the embrace of the dancers is getting stronger, and the tempo of the music is getting quicker, and the relationship is almost one in which there is barely a distinction left. The title of one of our papers was “Is Technology Becoming Science?” The answer is that, if it is not becoming science, it is certainly becoming very close to science, especially in the areas of hightech growth such as drugs and medicine, chemicals, and computing and communications. The areas which are leading the industrial growth of the West are just those areas that are very science intensive, and it is hard to imagine sustained industrial growth in any country without a strong competence in the scientific fields which so closely underlie these modern technologies.
F. Narin and D. Olilastro
/ Linkage between technology and science
It is also interesting to note that an argument can also be made here for the need to sustain a broad scientific capability. Although it is quite clear that different technologies depend heavily on rather industry-specific areas of knowledge, the boundaries between scientific fields are not clear, and a major technology such as professional and scientific instrumentation is drawing upon the resources of physicists, chemists, engineers and physicians, and all other parts of the basic research spectrum in developing and protecting its inventions. As a final point, in research which is still underway at CHI there is evidence suggesting the existence of a significant national component in science linkage. That is, there is some tendency for German-invented patents to cite German originated science, and for U.S.-invented patents to cite U.S. science, just as there is in the scientific literature a certain national component, and over-citing of each country’s scientific research by other researchers in the country. Certainly in science this is a completely natural phenomenon, reflecting the close developmental relationship between current research in a country, and earlier research in the country, which in science is often simply a reflection of the coherence of the streams of research within an individual university or research group. We expect to show in future papers that this local flow of research knowledge, which is so clear in basic science, also exists to a significant degree in the flow of national science into technology and, thus, in the future, to further delineate this rich and active relationship between these two facets of technical growth.
References [II M.P. Carpenter,
Patent citation as indicators of scientific and technological linkages, AAAS Annual Meeting, (Detroit, MI, USA, May 30 1983).
PI M.P. Carpenter
249
and F. Narin. Validation study: Patent citations as indicators of science and foreign dependence, World Patent information, 5 (3), (1983) 180-185. M. Cooper and F. Narin, Linkage he[31 M.P. Carpenter, tween basic research literature and patents, Research Management, 23 (2) (March, 1980) 30-35. [41 P. Collins and S. Wyatt, Citations in patents to the basic research literature, Research Policy, 17 (1988) 65-74. historically indepen[51 D.J. de Solla Price. Is technology dent of science? A study in statistical historiography. Technology Culture, 6 (1966) 553-56X. [61 F. Narin and E. Noma, Is technology becoming science’?, Scientometrics, 7 (3-6) (1985) 369-381. Patent citation [71 F. Narin, M. Rosen and D. Olivastro, analysis: New validation studies and linkage statistics, in: A.F.J. van Raan, A.J. Nederhof and H.F. Moed (eds.), Science Indicators: Their Use in Sclencr Policy and Their Role in Science Studies (DSWO Press, The Netherlands, November 1988). [81 D. Olivastro and F. Narin. Definition of Fields in Close Cooperation between Science and Technology (Bundesministerium fuer Forschung und Technologie, Bonn, Germany, August, 1989). [91 D. Olivastro and F. Narin, The Technological Utilization of European Science, First Interim Report (Centre National de la Recherche, Paris, France, October 1990). for journal 1101 G. Pinski and F. Narin, Citation influence aggregates of scientific publications: Theory, with application to the literature of physics. Information Processmg and Management, 12 (5), (1976) 297-312. illI Rer?ew and Assessment of the OTAF Concordunce between the U.S. Patent Classification and the Standard Industrial Classification Systems: Fmal Report, Office of Technology Assessment and Forecast, Patent and Trademark Office, (U.S. Department of Commerce, January 1985). and L.E. Birdzell Jr., Science, technology [121 N. Rosenberg and the western miracle, Scientific American, 263 (5) (November, 1990) 42-54. [I31 A.J. Toynhee. A Study of Hi.ytory (Oxford University Press, UK. 1962). [14] B.C. Van Vianen, H.F. Moed and A.F.J. Van Raan, An exploration of the science base of recent technology, Science Policy, 19 (1990) 61-81.