Patent analysis
Presenter: Huang Ming-Chao
Date: 06/25/2008
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Highlight of Patent analysis
 The content of patent data
Inventor
Assignee
Application/issued date
IPC/UPC
Reference/citation
 The unit of analysis
Firm-year level (cross-section & time series)
Patent level
Firm level
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The content of patent data
Backward citation
IPC
UPC
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Content
 Patent Analysis
 Firm-year level: Rosenkopf and Nerkar (SMJ, 2001)
 Firm level: Sampson (AMJ, 2007)
 Patent level: Millar, Fern & Cardinal (AMJ, 2007)
 Patent level: Phene, Fladmoe-Lindquist and Marsh (SMJ,
2006)
 Patent-based performance
Impact (backward citation)
Breakthrough innovation
Patent spell
Follow-on patenting
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Patent analysis:
Firm-year level
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Rosenkopf and Nerkar (SMJ, 2001)
 Industry: optical disk industry
 Framework
Technological domain
(Within or beyond)
Impact
(domain or overall)
Firm domain
(Within or beyond)
Technological boundary
Organizational boundary
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Rosenkopf and Nerkar (SMJ, 2001)
Framework
Backward citation
Forward citation
•Time frame: 1971-1995
Domain
Impact
Firm
domain
•USPTO database
•22 firms
•2,333 patents
Firm-year
Patent citations
Technological
domain
•371 firm-year observations
Overall
Impact
•Dependent variable: patent
count (exclude self-citation)
•Negative binomial regression
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Patent analysis:
Firm level
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Sampson (AMJ, 2007)
 Industry: telecommunication equipment industry (SIC classes-3661,
3663 and 3669)
 Alliance type: bilateral contract and equity joint venture.
Technological diversity
Inverse U
Innovation performance
Alliance type
 Data
 SDC
 MicroPatent
 Time frame: 1991-1993
 463 R&D alliances, 487 firms, 1,005 observations.
 Negative binomial regression
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Sampson (AMJ, 2007)
 Technological diversity
 Dependent variable
Post-alliance patents
innovative performance via
a count of citation-weighted
firm patents in a 4-year
post-alliance window,
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Patent analysis:
Patent level
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Phene, Fladmoe-Lindquist and Marsh (SMJ, 2006)
 Industry: biotechnology
industry
 Knowledge sourcing
 Technological space and
geographic origin
 Theory or perspective
Technological Technological
Proximate
distant
knowledge
knowledge
 Organizational learning
 Absorptive capacity
 Data
 Bioscan
 87 firms, 707 patents, 5988
backward citations, 4117
forward citations
5,988 backward
citation patents
707 focal patents
Filed in 1988
by 87 firms
4,117 forward
citation patents
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Patent analysis:
Patent level
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Millar, Fern & Cardinal (AMJ, 2007)
 Knowledge sourcing (boundary of firm and its divisions)
 Intra-divisional knowledge sourcing negatively affects forward citation
 Extra-organizational citation (positive effect)
 Inter-divisional citation (positive effect)
 Data
 NBER (National Bureau of Economic Research Patent Citations Data
File)
 MicroPatent Corporation





Time frame: 1985-1996
1,644 firms
211,636 patents (observations)
Unit of analysis: patent
Negative binomial regression
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Patent-based innovation performancePatent count
Impact
 Rosenkopf and Nerkar (2001)
 Domain impact equals the number of citations from optical disk
patents (that is, citing patents that were classified in any of our
initial optical disk subclasses) received by firm i’s patents
granted in year t.
 Overall impact is the total number of citations from non-optical
disk patents received by firm i’s patents granted in year t.
Breakthrough innovation
 Phene, Fladmoe-Lindquist and Marsh (2006)
 Forward citations, excluding self-citations.
 Every original patent has an equal 10-year time window for
citations. (citations received)
 Top 2 percent of the sample (15 original patents out of the total
of 707 patents) were identified as breakthrough innovations.
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Patent-based innovation performancePersistent innovation
Patent spell
 Alfranca, Rama and von Tunzelmann (Technovation,
2004)
 patent spells as periods of time during which the
company innovates year after year without gaps in its
activity.
Follow-on patenting
 McGrath and Nerkar (SMJ, 2004)
 Taking out a second patent in a patent subclass that is
new to the firm ( it has only one previous patent in a new
technological areas that it had not patented in before).
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