**6. Conclusion**

Our detailed examination of the E21B subclass has shown evidence of substantial differences in terms of the commercial potential of different types of upstream oil and gas technologies in the context of the Brazilian market. In addition, the findings on the robust growth of patent filings regarding upstream oil and gas technologies have provided evidence of a growing interest of firms operating in this particular industry in developing technical solutions to address specific operational challenges associated with the pre-salt

As mentioned above, it is possible to determine that within the scope of the E21B subclass, there are technologies that received greater attention from firms in the oil and gas industry, motivating more patent applications to protect inventions belonging to a small set of technical areas [39]. Clearly, we have identified a small number of highly active technical subareas that represent key technologies. However, the findings also point to several IPC classifications that comprise upstream oil and gas technologies, but did not motivate a growing number of patent applications. This was due to the existence of areas containing technologies not suitable to the Brazilian operational context of the pre-salt but also due to obsolete technologies that are

In practice, it was possible to identify technological hotspots within upstream oil and gas technologies [31]. Clearly, the technical subareas attracting the largest number of patent applications concern technologies designed to build and maintain wells, as well as technologies dedicated to increase productivity of existing wells. This can be seen as a strong evidence that operating companies are interested in improving technologies for building wells as maximizing production from oil formations. However, the findings also point out to that there are several technical areas attracting modest industry attention in a pre-salt context, such as percussion drilling, measuring the drilling time, preventing or extinguishing fires downhole in offshore conditions, and automatically arresting the fall of oil-well

The use of patent application figures helps us to claim that that the particular characteristics of the Brazilian pre-salt reservoirs generated specific perceptions of potential market demand for different technical areas. The concentration of patent applications in certain IPC groups, such as E21B 43 and E21B 33, highlights the value of these patents for business (Madani and Weber [51]). In fact, these patents can be perceived as instruments providing exclusive rights to commercialize critical technologies in an emerging and large-scale market. This way of perceiving decision-making regarding patenting leads us to the importance of highlighting the need to protect technologies that are perceived as strategic and generate expectations of

Thus, our research has revealed that despite the tremendous growth in patent applications concerning upstream oil and gas technologies in Brazil from 2007 onward, only a small set of very specific technical areas encompassed the wide majority of the patent applications. As such, this study contributed to the value of patent application figures as a robust performance indicator for monitoring competitive technology development efforts in the upstream oil and

exploration [9].

12 Drilling

tubing.

not motivating patent applications anymore [26].

high revenue potential in the coming years.

gas industry of a developing country.

This study provides further evidence of the value of exploring patent information. By exploring a sample of patent data related to upstream oil and gas technologies protected by different players in Brazil, valuable patterns were revealed. In practice, we have observed that the value of patent information goes beyond its role as a source of technical information by revealing insights of the attractiveness of certain technologies in a country. Evidence was also found that rival firms in the upstream oil and gas industry attempted to increase their competitiveness by reinforcing their patent portfolio with strategic technologies comprising high potential market value. Additionally, we believe that the paper is also valuable for readers without technical knowledge of upstream oil and gas technologies, as our study reveals patterns related to the relationship between market demand for technologies and the strategic use of patents.
