Optimal patent length and breadth in an economy with creative destruction and non-diversifiable risk

In this paper, I examine the optimal patent shape in an economy in which R&D firms innovate and imitate, households face non-diversifiable risk and there is externality in production and R&D. With non-diversifiable risk, a household’s consumption and investment decisions are interlinked. This economy contains industries of two kinds: monopoly industries with an innovator only, and duopoly industries with an innovator and an imitator. I define patent length as the expected time in which an innovation is imitated, and patent breadth as the innovator’s profit share in an industry after a successful imitation. The government can control patent length by the requirements for accepting a substitute for a patented good, and patent breadth by imposing compulsory licensing and royalties for the patentee after a successful imitation. I show that the stronger the externality in production relative to R&D is, the slower the optimal growth rate, the larger the optimal proportion of duopoly industries, and the longer and narrower the optimal patent.     

Patents and quality growth in OLG economy

This paper shows how heterogeneity in patent ownership across generations and lifecycle saving considerations qualitatively change the conventional implications of patent policy for quality growth. We study a close Overlapping Generations economy that grows through sequential quality improvements (“quality-ladder”), to show that for plausible values of the Inter-temporal Elasticity of Substitution (a) shorter patent length enhances growth (b) under exogenous innovation size loosening patent breadth protection spurs R&D investment and quality growth and (c) the effect of loosening lagging breadth protection on R&D investment and quality growth under endogenous innovation size depends on patents length. Our findings explore a new channel through which strong patents may hinder innovation and emphasize the importance of coordination in patent-policy across the different dimensions of the patents system.     

Uncertainty, Patent Length and Firm R&D: a Comment

In a recent paper, Goel (1996) analyses the effect of patent length on firm's R&D in a model where the timing of innovations is stochastic. He concludes that: 'Higher patent length does not necessarily lead to more R&D spending' (1996, p. 77). More precisely, 'in projects with high probabilities of innovation success firms might actually reduce their R&D spending when the patent length increases' (1996, p. 78). This conclusion, however, is flawed. The purpose of this note is to correct Goel's analysis, showing that in his model an increase in patent's length unambiguously leads to higher R&D investment.¹     

On R&D spillovers, multiple equilibria and indeterminacy

Empirical studies often find significant and positive R&D spillovers across firms. In this note, we incorporate this spillover effect into a scale-invariant quality-ladder model. We find that the modified model features multiple steady states (1) a high-R&D steady state, (2) a low-R&D steady state and (3) a zero-R&D steady state. As for dynamics, when R&D spillovers are small, only the zero-R&D steady state is stable, and it emerges as a no-growth trap. In this case, the economy is subject to sunspot fluctuations around this trap (i.e., local indeterminacy). When R&D spillovers are large, both the zero-R&D and high-R&D steady states are stable and locally indeterminate. In this case, increasing patent breadth may cause the high-R&D steady state to become unstable and the economy to converge to the no-growth trap. Therefore, strengthening patent protection may stifle innovation through the occurrence of a bifurcation.     

R&D policy with layers of economic integration

This paper examines whether the optimal unilateral R&D policy for an open economy is a subsidy or a tax. It constructs a general equilibrium model with three successive layers of international integration: (a) trade in goods, (b) trade in technologies with international R&D spillovers and (c) internationally-coordinated R&D policy. Trade in technologies introduces the possibility that an R&D subsidy will have such strong, negative terms-of-trade effects that it harms domestic welfare. Numerical simulations of the OECD show this is a possibility for the US and Japan. With international R&D spillovers a domestic R&D subsidy may reduce domestic innovation.     

Patent term extensions and commercialization lags in the pharmaceutical industry: A growth-theoretic analysis

Due to the lags in commercialization, the effective life of a patent is generally less than its statutory term. We introduce commercialization lags into the Schumpeterian growth model and explore the effects of patent term extensions on pharmaceutical R&D and social welfare. Our results show that extending patent terms stimulates the consumption of homogeneous goods but generates an ambiguous effect on the consumption of pharmaceuticals. When patent extensions have an inverted-U effect on social welfare, the optimal patent extension increases with the length of commercialization lags but decreases with the input intensity of commercialization lags. Finally, we calibrate the model and find that increasing patent breadth reduces the optimal patent extension.     

Types of patents and driving forces behind the patent growth in China

As a developing economy, China's unprecedented patenting surge is puzzling. We study China's patent surge and its driving forces using a novel and comprehensive merged dataset on patent applications filed by Chinese firms. We find that R&D investment, FDI, and patent subsidy have different effects on different types of patents. First, R&D investment has a positive and significant impact on patenting activities for all types of patents under different model specifications. Second, the stimulating effect of foreign direct investment on patent applications is only robust for utility model patents and design patents. Third, the patent subsidy only has a positive impact on design patents. The results imply that FDI and patent subsidy may disproportionately spur low-quality patents.     

Multistage R&D competition and patent policy

In this paper a model of multistage R&D patent policy is investigated. We study the impact of the duration of patent protection for intermediate products on R&D races when the discovery of the final product requires the accomplishment of an intermediate step. Using a multistage model where firms choose their levels of research investment at each stage, we find all subgame-perfect equilibria of the game. We also determine how competition affects a firm's level of research investment at different stages of the R&D competition.     

Effects of blocking patents on R&D: a quantitative DGE analysis

What are the effects of blocking patents on R&;D and consumption? This paper develops a quality-ladder growth model with overlapping intellectual property rights and capital accumulation to quantitatively evaluate the effects of blocking patents. The analysis focuses on two policy variables (a) patent breadth that determines the amount of profits created by an invention and (b) the profit-sharing rule that determines the distribution of profits between current and former inventors along the quality ladder. The model is calibrated to aggregate data of the US economy. Under parameter values that match key features of the US economy and show equilibrium R&;D underinvestment, I find that optimizing the profit-sharing rule of blocking patents would lead to a significant increase in R&;D, consumption and welfare. Also, the paper derives and quantifies a dynamic distortionary effect of patent policy on capital accumulation.     

Effects of a blocking patent on R&D with endogenous survival activities

This study analyzes the effect of strengthening patent protection for innovation and economic growth by introducing a blocking patent into the endogenous growth model developed by Furukawa (Econ Lett 121(1):26–29, 2013a), which features survival activity of patent holders in the R&D sector with a variety-expansion model. Results show that strengthening patent protection can raise the economic growth rate and social welfare through an endogenous survival investment. Additionally, this study examines the effects of increasing subsidies for R&D. We find that increasing R&D subsidy rate can negatively affect economic growth and social welfare because of the investment for survival activities. This result shows the novel role of a blocking patent in determining innovation effects of R&D subsidies. Furthermore, we analyze the effect of patent breadth which is another patent instrument in this model on innovation and economic growth. Results show that the growth and welfare effects of the profit-division rule and the subsidy rate for R&D may vary with the size of patent breadth.     

The Causality Between R&D And Investment

The aim of this paper is to investigate the relationship between R&D expenditure and investment in machinery and equipment in order to test for causality. New growth theory emphasises the role of R&D in creating blueprints needed to produce new capital goods implicitly assuming causality running from R&D to investment. Other recent studies using firm level data have investigated the relationship between innovative activity and investment in fixed capital. In this paper we use aggregate data from the US economy on R&D expenditure in the industrial sector and aggregate investment in machinery and equipment. Standard Granger causality tests, together with the Hsiao version, are then performed, showing that causality runs from R&D to investment. In addition we perform a cointegration analysis allowing a test of possible long-run feedbacks. This dynamic representation shows that any feedback between investment and R&D is only significant in the long run.     

Patents in a Model of Endogenous Growth

This paper examines patent protection in an endogenous-growth model. Our aim is twofold. First, we show how the patent policies discussed by the recent patent-design literature can influence R&D in the endogenous-growth framework, where the role of patents has been largely ignored. Second, we explore how the general-equilibrium framework contributes to the results of the patent-design literature. In a general-equilibrium model, both incentives to innovate and monopoly distortions depend on the proportion of industries that conduct R&D. Furthermore, patents affect the allocation of R&D resources across industries, and patents can distort resources away from industries where they are most productive.     

Strategic technology editing of the patent stage: lesson from a case of inkjet printer development

Patents are conventionally regarded as representing post-procurement of rights based on results of research and development (R&D). Patents can also be regarded as factors promoting R&D itself. In this study, the author examines the strategic meaning of patents in R&D through analyses of the R&D processes at Canon Inc., which is widely considered to submit patents strategically. The author identified characteristic behaviour related to patent acquisition in the R&D of inkjet printers. Canon constructed a strong patent group precisely by editing patents submitted earlier. Characteristic patent submissions were also identified: they elevated the obtained R&D results to higher concepts as milestones of R&D. These findings are discussed from the viewpoint of the meaning of patents for R&D and the possibility of effective R&D at the patent stage.     

Animal spirits and the composition of innovation in a lab-equipment R&D model with transition

We study the effect of animal spirits on the composition of aggregate R&D, the consumption level and economic growth in a tournament model of horizontal and vertical R&D. By considering a full lab-equipment specification, the model predicts a positive effect of animal spirits on the balanced-growth-path (BGP) level of per-capita consumption without impacting on economic growth and on aggregate vertical R&D. However, transition is slower under “waves of enthusiasm”, implying a longer period in which growth rates are higher than the BGP level. An economy that is subject to expectations shocks then converges at a time-varying speed. On average over time, transition is longer but less “painful”—i.e., with higher per-capita consumption levels—than otherwise.     

Patent claims and economic growth

This study introduces a blocking patent on horizontal R&D into the endogenous growth model of Chu et al. (2012), which features a blocking patent on vertical R&D. Results show that strengthening patent protection on horizontal R&D promotes vertical innovation (quality improvement) but hinders horizontal innovation (variety expansion). This effect of a horizontal blocking patent on directionality of innovation is opposite to that of the vertical blocking patent analyzed by Chu et al. (2012). Results also show that under mild conditions, strengthening a blocking patent on horizontal innovation as well as on vertical innovation can increase economic growth and social welfare.     

Innovation under the Climate Wise program

This paper examines the impact of participation in the Climate Wise program, one of the largest voluntary programs enacted in the US, on innovative activity by firms. In operation from 1993 to 2000, the Climate Wise program was designed to reduce greenhouse gas emissions by promoting innovation in energy efficiency and energy related activities. We begin by examining what types of firms were most likely to participate in this voluntary initiative. We find that the Climate Wise program was attractive to large firms, more R&D intensive firms, and firms with more financial resources. To consider the impact of Climate Wise participation on the innovative behavior of firms, we investigate whether participants and non-participants differed in the number of successful environmental and non-environmental patent applications between 1993 and 2003. We find some evidence that participation in the Climate Wise leads to a change in environmental patenting but only among less R&D intensive firms.     

Preemption,leapfrogging and competition in patent races

This paper investigates when patent races will be characterized by vigorous competition and when they will degenerate into a monopoly. Undersome conditions, a firm with an arbitrarily small headstart can preempt its rivals. Such ‘?-preemption’ is shown to depend on whether a firm that is behind in the patent race, as measured by the expected time remaining until discovery, cant ‘leapfrog’ the competition and become the new leader. An example of an R&D game with random discovery illustrates how ?-preemption can occur when leapfrogging is impossible. A multi-stage R&D process allows leapfrogging and thus permits competition. A similar conclusion emerges in a model of a deterministic patent race with imperfect monitoring of rival firms' R&D investment activities.     

R&D subsidies in a model of growth with dynamic market structure

This paper presents the effects of an R&D subsidy in a Schumpeterian general equilibrium model with rich industry dynamics. R&D subsidies raise the long-run growth rate, but they also raise the level of industry concentration. In the model firms compete for market share through process R&D endogenously determining the market structure within and across industries. Endogeneity of the market structure allows for analysis of changes in the moments of the firm size distribution in response to policy. R&D subsidies primarily benefit large incumbent firms who increase their innovation rates creating a greater technological barrier to entry. Concentration increases with fewer firms and a higher variance in the market shares. In general equilibrium, the greater distortions in the product market cause the wage rate to fall which leads to increased turnover rates. In addition, the analysis demonstrates that the model captures a large number of empirical regularities described in the industrial organization literature, but absent from most endogenous growth models. These features, such as entering firms are small relative to incumbents, the hazard rate of exit is negatively related to firm size, and large firms spend more on R&D than small firms play important roles in understanding the impact of R&D subsidies on the economy.     

The effects of consumption externalities in an R&D-based growth model with endogenous skilled and unskilled labor supply

We examine the roles of consumption externalities in a variety-expansion growth model. By assuming that the R&D sector is more skilled labor intensive than the consumption goods sector, we extend the model of Doi and Mino (J Econ Dyn Control 32:3055?C3083, 2008) so that both the skilled and unskilled labor supplies are endogenously determined through the skill acquisition process. We show that some results of Doi and Mino are influenced by our modification. For example, in contrast to Doi and Mino who show that the R&D subsidy can have a negative growth effect in the presence of consumption externalities, we show that the R&D subsidy has unambiguously positive growth effects, regardless of the presence of consumption externalities. Further, it is shown that the presence of consumption externalities influences various aspects of the economy including the wage inequality and the incentive of skill acquisition.     

Input and output additionality of R&D subsidies

This article analyses the effects of public R&D subsidies on R&D input and output of German firms. We distinguish between the direct impact of subsidies on R&D investment and the indirect effect on innovation output measured by patent applications. We disentangle the productivity of purely privately financed R&D and additional R&D investment induced by the public incentive scheme. For this, a treatment-effect analysis is conducted in a first step. The results are implemented into the estimation of a patent production function in a second step. It turns out that both purely privately financed R&D and publicly induced R&D show a positive effect on patent outcome.