本研究探討特斯拉的專利承諾授權對知識擴散的影響。專利承諾授權是專利持有者公開向大眾或特定群體授權其有效的專利，並有條件或無條件地收取或不收取合理的金額。此一授權方式已於各領域出現，如電信、軟體、生物技術，以及綠能科技等。在這種開放的授權方式下，承諾者通常有意推動某種技術的發展或是拓展其應用，因此本研究欲探究專利承諾授權是否能促進知識擴散。
本研究以專利引用數、專利引用的申請人數、三階CPC分類號三種觀察角度，探討特斯拉的專利承諾授權對知識擴散的影響。本研究假設，若特斯拉的專利承諾授權有助於知識擴散，則應能觀察特斯拉有承諾授權的專利，其於承諾後的引用數與引用的申請人數會明顯多於承諾前，也會明顯高於特斯拉未承諾授權的專利的引用數與引用的申請人數。特斯拉有承諾授權的專利，其於承諾後的引用涉及的、承諾授權專利所沒有的三階CPC分類號，應會多於承諾前，也會多於未承諾授權專利的引用涉及的、未承諾授權專利所沒有的三階CPC分類號。
觀察結果顯示，特斯拉有承諾授權的專利，確實有反映出上述的情形。這些觀察結果說明，特斯拉的專利承諾授權應有助於其承諾專利的知識擴散。上述的觀察似乎反映專利承諾授權對於知識擴散確實有所助益，但也不能否認，以上觀察限於特定產業，以及在該特定產業具有特殊的領導地位的企業，因此是否適用於其他承諾授權案例，還需更全面的調查。

This study estimates the effect of Tesla’s patent pledge on knowledge diffusion. A patent pledge is a license by a patent holder that out-licenses its valid patents to general public or to a specific group, with or without certain conditions or reasonable fees. This licensing approach has emerged in various fields, such as telecommunications, software, biotechnology and green technology. Under such an open licensing approach, pledgers generally intend to promote the development or application of certain technology. Therefore, this study aims to investigate whether patent pledges promote knowledge diffusion.
This study estimates the effect of Tesla’s patent pledge on knowledge diffusion from three observation perspectives: the number of citations, the number of applicants of the citations, and sub-classes of Cooperative Patent Classification (CPC). It is assumed that if Tesla’s patent pledge has an effect on knowledge diffusion, the number of citations of pledged patents and the number of applicants of those citations after the pledge will be significantly higher than before, and will also be significantly higher than those of unpledged patents. In addition, the number of sub-classes of CPC which the citations of the pledged patents after the pledge include while the pledged patents don’t, will be significantly higher than those before the pledge, and will also be significantly higher than those of the unpledged patents.
The observation results show that Tesla’s pledged patents reflect the above assumption, which means that Tesla’s patent pledge might contribute to the knowledge diffusion of its pledged patent. The observation results above seem to reflect that patent pledges facilitate knowledge diffusion, but it cannot be denied that they are limited to certain companies with leadership and in certain industries. Therefore, whether the observation results above are applicable to other cases of patent pledges still needs to be investigated more comprehensively.

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