ISSN 2434-2459

ISS Research Series No. 2

AGISSS
Gakushuin University
May ����

Spillover Pools and Patent
Application Activity in BusinessEnterprises
Kazuma Edamura

Association of Gakushuin International Social Sciences Studies
�- �- � Mejiro, Toshima-ku, Tokyo ���- ���� JAPANSpillover Pools and Patent Application Activity in Business Enterprises 1
By
Kazuma Edamura
Gakushuin University, Japan Productivity Center 2
Abstract
This study investigated whether technological management in the form ofindustry-academia-government collaboration is correlated with the results of research anddevelopment in Japanese industry. To accomplish this objective, utilizing data derived fromJapan’s Survey of Research and Development and the Institute of Intellectual Property’s
database, an empirical analysis of how spillover pools potentially available to businessenterprises affect their patent application activities, was performed. Incorporating theMahalanobis distance to take into account technological complementarity, the technologicalproximity between business enterprises was defined, and the spillover pools emanating fromindustry, academia, and government were respectively calculated. Designating the number ofpatent applications as the variable representing patent application activity, and consideringthat this variable constitutes non-negative count data, this study employed a panel poissonmodel to perform the estimations. The results demonstrated that spillover pools have apositive impact on patent application activity. Even when the respective spillover pools
created by industry, academia, and government were analyzed, a positive impact on patentapplications was evident. Further, this tendency remained intact, even when the spillover
pools were calculated according to research type, i.e. basic research, applied research, anddevelopment research.
Keyword: industry-academia-government collaboration, R&D, patent, spillover
1

This paper was prepared as part of the "Expansion and Analysis of Databases Classified According to
Geography and Industry Project" of the Research Institute of Economy, Trade, and Industry (Independent
Administrative Agency). Having completed this study, the author wishes to thank his fellow participants in the
project. Further, the author also wishes to thank his fellow participants at the IIPR workshops held on August 4,
2016 and March 15, 2017, for their comments and advice. The author gratefully acknowledges financial
assistance received from the Japan Society for the Promotion of Science (JSPS) Grants-in-Aid for Scientific
Research Program: (C-No. 16K03692) and (C-No. 16K03882); and Grant-in-Aid for Challenging Exploratory
Research (No. 15K13018).
2

kazuma.edamura@jpc-net.jp
1

1. Introduction
Since Chesbrough (2003) propounded the importance of open innovation, various
policies have been implemented toward its realization. As defined by Chesbrough, “openinnovation is the use of purposive inflows and outflows of knowledge to accelerate internalinnovation, and expand the markets for external use of innovation, respectively.” The“business enterprises” referred to need not be restricted to business organizations, but may
encompass a wider range of organizations, including universities and public institutions. The
continuing discourse surrounding open innovation forms the theoretical backdrop forindustry-academia-government collaboration. However, in an analysis of open innovation,
there is a need to explore the spillover effect and the extent to which the knowledge
belonging to outside organizations may be acquired. If there is no spillover of knowledge
from universities and public research institutions, business enterprises cannot avail of “theuse of purposive inflows and outflows of knowledge”. However, due to the limited data
available, the extent to which knowledge from universities and public research institutions isbeing used by business enterprises has not been quantified.
This study attempts to quantitatively measure the spillover from business enterprises,
universities, and public research institutions, using data from Japan’s Survey of Research andDevelopment (hereinafter, the “Survey”). Further, utilizing the Institute of Intellectual
Property’s (IIP) database, it clarifies whether the spillover of research results fromuniversities and public research institutions affects patent application activity. Specifically,
adopting the spillover pool concept originated by Bloom, Schankerman, and Van Reenen(2013) as a spillover indicator, this study measures the respective spillover pools flowing
from business enterprises, universities, and public research institutions. Next, it focuses on
the spillover pools of universities and public institutions from which business enterprises canobtain knowledge, as well as their effect on the number of patent applications submitted, andanalyzes them statistically in light of various other factors.
Jaffe (1986), Audretsch and Feldman (1996), and Bloom et al (2013) have performed
empirical analytical studies of spillover effects on industrial research and development(R&D). All of these studies highlighted the potential role of spillovers in promoting industrial
R&D. However, spillovers may be constrained by geographical factors (Almeida and Phene,2004). When the knowledge sources are near each other, a business enterprise’s researchers
can communicate better with outside researchers, and receive spillovers more efficiently2

(Almeida and Phene, 2004). In many cases, research results are embedded as tacit knowledge
in the researchers themselves, in which case interaction among the researchers leads tospillovers (Almeida and Kogut, 1999). Since the closer the researchers are to each other, theeasier the interaction becomes, geographical distance from the knowledge sources influences
spillovers (Singh, 2005).
Previous studies have considered spillovers solely within the industrial sphere, but there
has been no comprehensive analysis of spillovers from universities and research institutions
to business enterprises. Research focusing on spillovers from universities and research
institutions to business enterprises exists, but the samples have been limited, and no empiricalanalysis of panel data at the industrial level has been performed. This study attempted toelucidate and quantify spillovers business enterprises can absorb from universities andresearch institutions.
To quantify the spillover pools of universities and research institutions from whichbusiness enterprises can absorb knowledge, this study used data from the Survey’s specificquestionnaires. The Survey compiles the number of researchers and the amount of researchexpenditures in the various fields of research undertaken by business enterprises, universities,
and public research institutes. By weighting and totaling the intramural research expenditures,the spillover pools were quantified. Using the IIP patent database, the number of patentapplications classified according to industry and year of application were aggregated.
Matching the Survey’s specific data with the IIP patent database, the effects of the spillover
pools that business enterprises receive from outside organizations, on patent application
activity, was statistically derived, while taking into account the research inputs, the businessenterprise’s scale, the attributes of the industry to which the business enterprise belongs, andtrends.
Considering that the number of patent applications is a non-negative integer, and the data
used in the analysis are panel data, a panel poisson model was selected for the estimations.
The results suggested that an increase in the spillover pools that a business enterprise canreceive from outside organizations causes an increase in the business enterprise’s patentapplications. If the spillover pools are broken down by source, i.e. business enterprises,
universities, and public research institutions, and a similar analysis is performed, the results
likewise indicate that an increase in each institution’s spillover pool causes the businessenterprise’s patent applications to increase. Further, if the intramural research expenditures3

are classified according to basic research, applications research, and development research,
the spillover pools measured also have a positive impact on the number of patent applications.
There was no difference observed in this trend.
The structure of this paper is as follows. Part 2 organizes the Survey data relating tobusiness enterprises, universities, and public research institutions, their individual intramuralR&D expenditures, and captures the spillover pool each sector receives. Part 3 describes theestimation model and the specification method for the variables. The estimation results arepresented in Part 4, and Part 5 elaborates on this study’s conclusions based on those results.

2. Intramural Research Expenditures of Industry-Academia-Government andSpillover Pools
This study quantitatively analyzed the influence of spillover pools from businessenterprises, universities, and pubic research institutions on patent application activity. To
accomplish this, the intramural research expenditures of business enterprises, universities,
and pubic research institutions were determined. In Japan, the business enterprises,
universities, and pubic research institutions are surveyed under the Statistics Act by theprincipal statistical survey called “Survey or Research and Development”. Based on the
Frascati Manual, the internationally recognized statistical standard, this Survey collects
information on Japan’s R & D, using a universally accepted methodology to survey businessenterprises, universities, and public research institutions. For business enterprises with acapital of ¥ 1 million or more but less than ¥ 100 million, the survey is based on sampling,
while for business enterprises with a capital of ¥ 100 million or more, the survey is universal.
The survey covered all of the universities in Japan 3. All of the public research institutions
surveyed were also located in Japan 4. Since the 2002 survey (on actual 2001 data), by
submitting an application for secondary use, the registered information may now be used, andthe survey items pertaining to the research activities of business enterprises, public research3

The universities covered by the Survey include university colleges and faculties, research departments at
graduate schools, junior colleges, colleges of technology, research centers attached to universities, researchfacilities attached to universities, inter-university research institute corporations, independent administrative
agencies, and national institutes of technology.
4

The public research institutions covered by the Survey are those specified in materials issued by regional /local governments and public organizations.
4

institutions, non-profit organizations, and universities can be linked to other databases andanalyzed statistically. This study was mainly focused on the analysis of business enterprises,
universities, and public research institutions.
The Survey covers the intramural research expenditures of business enterprises,
universities, and public research institutions. Figure 1 shows a history of the total intramuralresearch expenditures of business enterprises, public research institutions, and universities,
based on the Survey’s results. The inclusion of data from public research institutions only
began in 1998, when they were transformed into independent administrative agencies.

Tocompare the intramural research expenditures of business enterprises, public research
institutions, and universities, the history of their total intramural expenditures since 1998
were tabulated. The statistics showed that business enterprises are the principal players inJapanese R&D expenditures, accounting for approximately 70% of the total. This tendency
was constant between 1998 and 2013. After business enterprises, universities and public

2000

4000

billion yen
6000
8000

10000 12000

research institutions followed in the magnitude of their R&D expenditures.

1998

2000

2002

Industry

Figure 1.

2004

2006
Year

2008

Public research inst.

2010

20122013
Universities

Intramural R&D Expenditures of Industry-Academia-Government

5The Survey breaks down intramural R&D expenditures into basic research, appliedresearch, and development research expenditures, and surveys the expenditures of businessenterprises, public research institutions, and universities, classified into each of the above
categories. Figures 2~4 show the amounts and ratios of the expenditures of businessenterprises, public research institutions, and universities for basic research, applied research,and development research. An examination of Figure 2 concerning business enterprises
reveals that the greater part of their expenditures is for development research, followed byapplied research and basic research. However, the proportion allocated to basic research ismeager. On the other hand, Figure 3 concerning universities shows that half of theirexpenditures is devoted to basic research, followed by applied research and development. In
contrast with business enterprises, basic research accounts for the great majority of theexpenditures, and the proportion of development research expenditures is low. As for the
expenditures of public research institutions shown in Figure 4, most of the expenditures areallotted to development research, although this proportion of intramural R&D expenditures isa little less than half. These expenditures are followed by substantial expenditures for appliedresearch and basic research in order of magnitude. Although the proportion allotted to appliedresearch is slightly lower, relative to basic research, the amounts are almost the same. A
comparison of intramural R&D expenditures among these sectors reveals significant
differences in the spheres where business enterprises, universities, and public research
institutions conduct their R&D. It is said that business enterprises are mainly engaged indevelopment, while universities mainly conduct basic research. Let us verify this observationon the basis of their expenditures.

6

Figure 3.

7

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

500

billion yen
1,000
1,500

2,000

Figure 2.

1999

1998

0

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

0
5,000

billion yen
10,000Development

Applied
Basic

Breakdown of R&D expenditures in Business Enterprises

Development

Applied
Basic

Breakdown of R&D expenditures in Universities

15,0002,5002,000
billion yen
1,000
1,500

Development

Figure 4.

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

0

500

Applied
Basic

Breakdown of R&D expenditures in Public Research Institutions

Next, using the Survey’s data, the spillover pools that business enterprises, universities,
and public research institutions can avail of were calculated, and their history was traced.
Using the method devised by Bloom, Schankerman, and van Reenen (2013), the Mahalanobis
distance denoting technological proximity was defined and used as a weight factor to derive
the total weighted R&D expenditures 5 . In the past, as in Jaffe (1986) and Bloom,
Schankerman, and van Reenen (2013), the number of patents in each technological fieldaccording to international patent classifications were being used. However, as pointed out by
Bloom, Schankerman, and van Reenen (2013), spillovers naturally occur among researchers;
hence, the closer their specializations are, the easier it is for spillovers to occur. The
spillovers that can occur among business enterprises, universities, and public research
institutions consist of the totality of knowledge spillovers among those researchers. By using
data on the number of each organization’s researchers, classified according to their fields,
5

The research expenditures were derived using the Ministry of Education’s “Japanese Research Expenditure
Deflators (Comprehensive, including Humanities and Social Sciences)” (2015).
8

spillovers can be measured more accurately. This study measures technological proximity byusing data on the number of specialized researchers reported in the Survey on Research andDevelopment.
Among the previous studies, many focused solely on spillover pools among businessenterprises, omitting spillovers from universities and public research institutions. This may be
attributed to the fact that the necessary data regarding patent bibliographies and R&D
expenditures of business enterprises are relatively more accessible, while data on universities
and public research institutions are more difficult to obtain. Since spillovers emanate not only
from business enterprises, but also, from universities and public research institutions, if
possible, the latter should also be examined. This study used data on business enterprises,
universities, and public research institutions compiled by the Survey on Research andDevelopment, to quantify and analyse spillover pools from universities and public research
institutions which have not been covered by previous studies.
First, the technology vector is defined as follows:=
Ti[Ti1 , Ti 2 ,..., TiK ]  1× K

Here, for instance, Tik represents the share of researchers in the specialization k belonging toorganization i in a particular year. T(K,N) represents the sequence specified for the businessenterprises, universities, and public institutions. N represents the number of organizations in aparticular year. If the 3 sectors of business enterprises, universities, and public research
institutions are each identified as 1 entity at the macro level, N = 3. If each businessenterprise, each university, and each public research institution is considered at the microlevel, this would the the total number of business enterprises, universities, and public research
institutions.
Next, T is formalized as follows:
T

 T′

TN′
T2′
1
 K×N
,
,...,

12
12
12 
(TN TN′ )  (T1T1′) (T2T2′ )  ′ denotes the uncentered correlation measure among the technology fields, originated byTT
Jaffe (1986).

9Here, T(:,i) is the iteration i of T, and the sequence is defined as:

X



′
′
′
T(:,1)
T(:,2)
T(:,N)


 K×N
,
,...,
12
 (T T ′ )1 2 (T T ′ )1 2

′
T
T
(
)
(:,2) (:,2)(:,N) (:,N)
 (:,1) (:,1)
Using this sequence, with  ′  K × K , we arrive at the Mahalanobis normed technology closeness=Ω XX
M= T ′ΩT . Here, the Mahalanobis normed technology closeness for organization i andorganization j becomes lower as it approaches 0, and higher as it approaches 1. Using theMahalanobis normed technology closeness M as the weight factor, we derive the weighted
total of organization j’s R&D expenditures Rj ( j ≠ i ), and define this as the spillover pool Si
that organization i can use:
S i = ∑ M ij R jj ≠iHere, we considered business enterprises, universities, and public research organizations
as organizations at the macro level. We determined the aggregate total of specialized
researchers and the intramural R&D expenditures of business enterprises, universities, andpublic research organizations, based on their respective data, and calculated the spillover pool,taking into account the Mahalanobis distance. Figure 5 shows the yearly spillover pools fromacademia and government that business organizations can use. An examination of thesespillover pools from universities and public research organizations available to businessenterprises reveals an increasing tendency. Even after the Lehman Shock of September 2008
and the Great East Japan Earthquake of March 2011, the spillover pools continued increasing.
Although the Lehman Shock and the Great East Japan Earthquake led business enterprises toreduce their intramural R&D expenditures, universities and public research institutions
increased their intramural R&D expenditures, resulting in the expansion of the spillover pools
available to business enterprises.

1020
trillion yen
1015

Universities

1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013

0

5

Public research inst.

Figure 5.

Spillover Pools from Universities and Public Research Institutions

Available to Business Enterprises

Figure 6 shows the spillover pools from business enterprises and public research
institutions available to universities, revealing that almost all of the spillover pools
universities can avail of originate from business enterprises. Due to the Lehman Shock,spillover pools from business enterprises decreased, resulting in smaller spillover pools
available to universities. However, an increasing trend has subsequently reappeared.

11

100
80
trillion yen
40
60

Universities

Figure 6.

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

0

20

Industry

Spillover Pools from Business Enterprises and Public ResearchInstitutions Available to Universities

Figure 7 shows the spillover pools from business enterprises and universities available topublic research institutions. As in the case of spillover pools available to universities, almost
all of the spillover pools available to public research institutions originate from businessenterprises. Similarly with the universities, due to the Lehman Shock, the spillover pools
from business enterprises decreased, and the spillover pools available to public research
institutions diminished. However, an increasing trend subsequently reappeared.

12

50
40
trillion yen
20
30

Public research inst.

1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013

0

10

Industry

Figure 7.

Spillover Pools from Business Enterprises and Universities Available to
Public Research Institutions

3. Estimation Model and Data
3.1 Estimation ModelTo quantitatively analyze the effects of spillover pools available to business enterprises
on patent application activity, this study used the following model based on the equation used
by Jaffe (1986) and Bloom, Schankerman, and Van Reenen (2013).
Pit = α Sit + β Rit + γ X it + ε it
However, Pit represents the number of patent applications submitted by business enterprise iin year t. S represents the spillover pool, while R is the variable for the scale of R&D inputs.
X represents the control variable.

13

Considering that when the above model performs estimations at the business enterpriselevel, the number of patent applications P, the response variable, is a non-negative integer
constituting count data, we decided to use a poisson model. For count data models, negative
binomial models may also be used. However, as it is presumed in a poisson model that the
average and dispersion values are identical, the negative binomial model is more universal.
Allison and Waterman (2002) and Guimaraes (2008) have pointed out that as a panel countdata model, the negative binomial model is biased. When an analysis using panel data is to be
performed, there is no consensus as to whether a poisson model or a negative binomial model
should be adopted. Based on the opinions of Allison and Waterman (2002) and Guimaraes(2008), this study selected a panel poisson model for its estimations.

3.2

Data
Applying the patent equation described above to estimate the impact of spillover poolson the number of patent applications, this study used the Survey’s specific questionnaire data.
As described above, the Survey provides data relating to R&D activity, e.g. number of
researchers per research type, R&D expenditures, etc., and basic data, e.g. number of
employees and the industry to which the business enterprise belongs. The Survey’s
Questionnaire A data relating to business enterprises were used in the estimations. The data
used in this study’s analysis covered the period from 2001-2011 and reflected patent data
extracted from the IIP patent database described below, complementing the registered data
available for the period. Business enterprises in the manufacturing industry were the subjectof this analysis. Since panel data analysis was involved, the subject companies must havesubmitted 1 or more applications during the period, and the sample data for the past 2 years
or more must have been available.
The number of patent applications was obtained from the publicly accessible Institute ofIntellectual Property database (IIP Patent Database). Each patent’s bibliographic data isregistered in the IIP database. Using data regarding the patent applicants and the application14

year, the patent data was aggregated at the applicant level and at the application year level.
This study discovered that the number of patent applications dramatically decreased from2011 to 2012. The more recent the patent application is, the less likely it is to be alreadyregistered in the database, resulting in a truncation bias. For this reason, this study only
extracted data until 2011 for its analysis.
In order to mesh the Survey’s data concerning researcher mobility and R&D with thenumber of patent applications extracted from the IIP database for the analysis, the Survey’s
specific questionnaire data, organized as panel data at the business enterprise level, must be
matched with the IIP database data, organized as panel data at the patent applicant level. This
study used the business enterprise’s name and the patent applicant’s name registered in theSurvey as keys in the matching process 6.

As a result of the matching, unbalanced panel dataconsisting of 38,199 samples relating to 5,685 business enterprises from 2001 to 2011 wereobtained.
As an indicator of the business enterprises’ R&D inputs, the R&D expenditure stock wasused in this study. The business enterprises’ intramural R&D expenditures data available
from the Survey constituted the stock, based on the perpetual inventory method, as follows:

Rit = (1 − δ ) Eit −1 + Eit
However, Eit represents the expenditures of business enterprise i during year t. Further, δrepresents the obsolescence rate. This study adopted the 20% obsolescence rate proposed byCorrado, Hulten, and Sichel (2009).
This study subsumed the business enterprise’s scale and attributes, as well as trends, into
the control variables used in the patent formula. For the business enterprise’s scale, the6

When the names of business enterprises and patent applicants were used in the matching, variations such as“Corporation” and “Inc.” were smoothed out. Further, to facilitate more accurate matching, the inclusion ofaddress data could have been possible, but this study did not include them. While the Survey asks for theaddress of the business enterprise’s principal research center, the patent applicant usually specifies the addressof the business enterprise’s headquarters, so matching cannot be done on this basis. For this reason, in thebusiness enterprise data used by this study, entities with identical names could not be properly analyzed. Thisremains a topic for future consideration.
15

number of employees registered in the Survey was used. For the business enterprise’s
attributes, using the information available from the survey, a dummy variable for the industry
to which the business enterprise belongs, was incorporated into the model. To take trends into
account, a dummy for the years was used.

4.

Estimation Results
The variables used in this study’s estimation were derived from the Survey’s specificquestionnaire data and the IIP database. The basic statistics are presented in Table 1. After
referring to methods used in previous studies, this study examined the spillover pools
reflecting technological proximity, defined using the International Patent Classification (IPC),
and the spillover pools defined using data on researchers classified according to research typein the Survey. A comparison between the spillover pools calculated according to the IPC, andindustry-academia-government spillover pools from business enterprises, universities, andpublic research institutions, calculated using data on researchers classified by research type,revealed that the average for the former was ¥595,000,000,000, and ¥5,095,000,000,000 forthelatter,denoting

anenormous

difference.

Classified

accordingtoindustry-academia-government sources, the spillover pools available to business enterprises
amounted to ¥4,155,000,000,000 from other business enterprises, ¥420,000,000,000 fromuniversities, and ¥521,000,000,000 from public research institutions. The spillover pools
available from other business enterprises comprised 80% of the total, while the spillover
pools available from universities and public research institutions accounted for 20%. The
results derived above, not only for business enterprise but also for universities and publicresearch institutions, enabled an analysis spillover pools from various viewpoints.
As described in Section 2, the expenditures of business enterprises, universities, andpublic research institutions are characteristically allocated into basic research, appliedresearch, and development research. This study analyzed the effects of the spillover pools
generated by the expenditures in these research categories on the number of patent16

applications submitted by business enterprises. Further, this study classified the expendituresof business enterprises, universities, and research institutions into these 3 research types, andanalyzed in detail their effects on the number of patent applications.

Table 1.

Basic Statistics

Patent application
Spillover pool using IPC (trillion yen)
SP_ipcSpillover pool using researcher information (trillion yen)
SP_total
SP_basic (for basic research)
SP_applied (for applied research)
SP_develop (for development research)
SP_ind (by industries)
SP_uni (by universities)
SP_pub (by public research institutes)
SP_basic_ind (for basic research by industries)
SP_basic_uni (for basic research by universities)
SP_basic_pub (for basic research by public research institutes)
SP_applied_ind (for applied research by industries)
SP_applied_uni (for applied research by universities)
SP_applied_pub (for applied research by public research institutes)
SP_develop_ind (for development research by industries)
SP_develop_uni (for development research by universities)
SP_develop_pub (for development research by public research institutes)
R&D (billion yen)
employment (thousand)Obs.
38,199mean
65.002s.d.
423.940

min
0

max
15093

38,199

0.595

0.716

0.000

5.025

38,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,19938,199

5.095
0.526
1.056
3.421
4.155
0.420
0.521
0.233
0.194
0.099
0.818
0.101
0.138
3.100
0.047
0.273
13.303
0.905

3.315
0.278
0.647
2.391
2.826
0.249
0.296
0.132
0.109
0.058
0.525
0.062
0.075
2.188
0.031
0.181
90.3812.804

0.000
12.268
0.000
1.327
0.000
2.593
0.000
8.327
0.000
10.253
0.000
1.372
0.000
1.340
0.000
0.581
0.000
0.601
0.000
0.336
0.000
2.064
0.000
0.483
0.000
0.367
0.000
7.645
0.000
0.135
0.000
0.713
0.000 3286.730
0.001
80.449

Tables 2 and 3 shows the estimation results from the patent formula, using the spillover
pools calculated based on the Survey’s Questionnaire A data on business enterprises,
Questionnaire B data on public research institutions, and Questionnaire C data on universities,
and the number of patent applications at the business enterprise level extracted from the IIP
database. Model [1] excluded the spillover pools and included only the intramural R&D
expenditure stock and the number of employees. In this model and all of the other models, thecoefficients for the intramural R&D expenditure stock and the number of employees werepositive and therefore significant. This signifies that using the intramural R&D expenditurestock and the number of employees as the respective control variables for the scale of R&D
inputs and the business enterprise’s scale did not cause any problems in the model.

17An examination of the coefficients relating to the spillover pools shows that in all of themodels from model [2] to model [8], these coefficients were positive and therefore significant.
In model [2], the spillover pool coefficients derived as usual by using IPC, were positive andtherefore significant. In model [3], which used spillover pools derived from the number of
researchers classified by research type, the coefficients were also positive and therefore
significant. Hence, there was no substantial difference in the signs of the coefficients causedby differences in technological proximity. In models [4], [5], and [6], the results showed that,even when broken down into basic research, applied research, and development research, therespective coefficients were positive and therefore significant. Similarly in models [8] and [9],the results showed that in the case of spillover pools available to business enterprises fromother business enterprises, universities, and public research institutions, the respective
coefficients were positive and therefore significant.
Models [10] to [18] show the estimation results for 9 categories based on data regarding
expenditures classified by research field, and spillover pool data classified according to otherbusiness enterprises, universities, and research institutions. All of the coefficients werepositive and therefore significant. The value of the partial standard regression coefficient
representing the increment when the standard deviation becomes 1, was almost identical ineach model.
The positive spillover pool coefficients signify that when business enterprises other than
the subject business enterprise, universities, and public research institutions conduct theirresearch activities, the subject business enterprise’s patent applications increase in number.
This tendency is identical even when the spillover pools from other business enterprises,
universities, and public research institutions are broken down into basic research, appliedresearch, and development research. Based on the above observations, business enterprises
avail themselves thoroughly of the research activities of other business enterprises,
universities, and public research institutions, and intensify their patent application activities.
Moreover, not only the development research predominantly conducted by business18

enterprises, but also spillovers from basic research and applied research are widely utilized,
potentially promoting patent applications.

19

Table 2.

Estimation Results (1)
[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

Spillover pool using IPC
SP_ipc0.2657***[0.0004](0.0023)

Spillover pool using researcher info.
0.0744***[0.0006](0.0006)

SP_total

0.7990***[0.0005](0.0061)

SP_basic

0.3688***[0.0006](0.0031)

SP_applied

0.1028***[0.0006](0.0009)

SP_develop

0.0861***[0.0006](0.0008)

SP_ind

0.7748***[0.0005](0.0067)

SP_uniSP_pub

R&D

Employment
Inudstry dummies
Year dummies
observation# of firm

0.0004*** 0.0002***[0.0001][0.0000](0.0000)(0.0000)
0.0234*** 0.0168***[0.0002][0.0001](0.0003)(0.0003)
Yes
Yes
Yes
Yes
38199
38199
5685
5685

0.0003***[0.0001](0.0000)
0.0199***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0209***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0202***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0198***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0200***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0206***[0.0001](0.0003)
Yes
Yes
38199
5685

0.7722***[0.0005](0.0061)0.0004***[0.0001](0.0000)
0.0200***[0.0001](0.0003)
Yes
Yes
38199
5685

※ Coefficients are not enclosed in brackets or parentheses. Square brackets denote standard partial regression coefficients. Round brackets denote standard deviations.
20

*** denotes a significance level of 1%.

Table 3.

Estimation Results (2)
[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

Spillover pool using researcher info.
SP_basic_ind

1.6230***[0.0005](0.0133)
1.9065***[0.0005](0.0152)

SP_basic_uni

3.2766***[0.0004](0.0267)

SP_basic_pub

0.4491***[0.0006](0.0039)

SP_applied_ind

3.4327***[0.0005](0.0298)

SP_applied_uni

2.5700***[0.0005](0.0216)

SP_applied_pub

0.1113***[0.0006](0.0010)

SP_develop_ind

6.5768***[0.0005](0.0601)

SP_develop_uni

SP_develop_pub

R&D

Employment
Inudstry dummies
Year dummies
observation# of firm

0.0003***[0.0001](0.0000)
0.0218***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0003***[0.0001](0.0000)
0.0200***[0.0001](0.0003)
Yes
Yes
38199
5685

0.0004*** 0.0003*** 0.0003*** 0.0003***[0.0001][0.0001][0.0001][0.0001](0.0000)(0.0000)(0.0000)(0.0000)
0.0219*** 0.0201*** 0.0208*** 0.0213***[0.0001][0.0001][0.0001][0.0001](0.0003)(0.0003)(0.0003)(0.0003)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
38199
38199
38199
38199
5685
5685
5685
5685

21

0.0003***[0.0001](0.0000)
0.0199***[0.0001](0.0003)
Yes
Yes
38199
5685

1.2883***[0.0006](0.0111)0.0003*** 0.0004***[0.0001][0.0001](0.0000)(0.0000)
0.0211*** 0.0190***[0.0001][0.0001](0.0003)(0.0003)
Yes
Yes
Yes
Yes
38199
38199
5685
5685

※ Coefficients are not enclosed in brackets or parentheses. Square brackets denote standard partial regression coefficients. Round brackets denote standard deviations.
※ *** denotes a significance level of 1%.

22

5. Conclusions and Discussion
Utilizing a patent formula and the Survey on Research and Development’s dataon the number of researchers by research type to calculate spillover pools, not only
from business enterprises but also from universities and public research institutions,the effects of spillover pools on the number of patent applications submitted bybusiness enterprises were estimated. Considering that the number of patentapplications is a non-negative integer, and that the business enterprises areheterogeneous, the data for analysis was organized as panel data at the businessenterprise level and the application year level, and the estimations were performed bya panel poisson model. The results demonstrated that increases in the spillover pools
available to business enterprises lead to increases in their patent applications. Further,
it was observed that if the spillover pools available to business enterprises are broken
down according to research type, i.e. basic research, applied research, anddevelopment research, their respective increases also result in an increase in patentapplications. Moreover, if the spillover pools available to business enterprises areclassified according to source, i.e. other business enterprises, universities, and publicresearch institutions, their respective increases also statistically indicate an increase inpatent applications. The conclusion that increases in spillover pools have a positive
impact on increasing patent applications does not change, even when there aredifferences in the data on research expenditures by research type, and differencesamong the external organizations.
This study’s estimation results demonstrating that spillover pools promote patentapplication activity in business enterprises is consistent with relevant prospective
studies. This study shows that to improve R&D efficiency, business enterprises caneffectively exploit external knowledge and avail themselves of spillovers. Further,apart from the spillover from other business enterprises that a business enterprise can
exploit, which various prospective studies have analyzed, this study showed thatbusiness enterprises can avail themselves of spillovers from universities and public
23

research institutions while conducting their patent application activities. This study
also quantitatively demonstrated that the research activities of universities and publicresearch institutions exert a significant influence on the research activities of businessenterprises.
The estimation results obtained from this study are highly significant for thedetermination of corporate R&D policies, as well as policies to promote scientific andtechnological innovation. These results showing that business enterprises preparing
patent applications can exploit the results of R&D activities conducted by universities
and public research institutions indicate that industry-academia-government
collaboration can foster more efficient patent application activities on the part ofbusiness enterprises. Through industry-academia-government collaboration, businessenterprises can communicate closely with researchers in universities and publicresearch institutions. If a greater understanding of external knowledge is nurtured,business enterprises can more efficiently manage their R&D efforts and patentapplication activities. Although this study’s results suggest that collaboration among
business enterprises themselves may have a positive effect on their patent application
activities, whether this positive effect will materialize or not depends largely on theinterrelationships among the collaborating business enterprises. Competition between
business enterprises on one hand, and universities and public research institutions on
the other, is unlikely. Meanwhile, relationships among business enterprises arehandled on a case-by-case basis. There are numerous possible scenarios, e.g.
collaboration between rivals, between parent companies and subsidiaries, and between
companiesin

different

industries.

There

is

a

high

probability

that

industry-academia-government collaboration, as a policy, functions to effectively
promote patent applications. However, the implementation of a policy ofcollaboration among business enterprises in the same industry cannot be universal.

24

Reference
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Almeida, P. and Phene, A. (2004) “Subsidiaries and Knowledge Creation: theInfuluence of the MNC and Host Country on Innovation,” Strategic Management
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Bloom N., Schankerman M., and J. Van Reenen (2013) “Identifying Technology
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Jaffe A. (1986) “Technological Opportunity and Spillovers of R&D: Evidence fromFirms’ Patents, Profits, and Market Value.” American Economic Review,984-1001.
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Patterns,” Management Science, pp.756-770.

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