Such licenses and other contracts may be the subject of disagreements with the grantors and/or various third parties regarding the interpretation of such licenses and contracts. The resolution of any such disagreements that may arise could affect the scope of our rights to the relevant technology, or affect financial or other obligations under the relevant agreement, either of which could inhibit our ability to utilize the underlying technology in a cost-effective manner to develop and commercialize our product candidates, which in turn could materially adversely affect our business, financial condition, results of operations and growth prospects.
Our existing license agreements impose, and we expect that our future license agreements will impose, various diligence, milestone payment, royalty, insurance, indemnification and other obligations on us. Under certain circumstances such as a material breach of terms, our licensors could terminate our license agreements. If these in-licenses are terminated, or if the underlying patents fail to provide the intended exclusivity, competitors could have the freedom to seek regulatory approval of, and to market, products substantially the same as or identical to ours. In addition, we may seek to obtain additional licenses from our licensors and, in connection with obtaining such licenses, we may agree to amend our existing licenses in a manner that may be more favorable to the licensors, including by agreeing to terms that could enable third parties (potentially including our competitors) to receive licenses to a portion of the intellectual property that is subject to our existing licenses.
In addition, we may not have the right to control the preparation, filing, prosecution, maintenance, enforcement and defense of patents and patent applications directed to the technology that we license from third parties. Therefore, we cannot be certain that these patents and patent applications will be prepared, filed, prosecuted, maintained, enforced and defended in a manner consistent with our best interests. For example, if we do not have the right to control patent prosecution and maintenance of patents and patent applications directed to the technology that we license from licensors, such licensors could file terminal disclaimers and/or take other actions that could shorten the term of the patents or patent applications. If our licensors fail to prosecute, maintain, enforce and defend such patents, or lose rights to those patents or patent applications, the rights we have licensed may be reduced or eliminated, and our right to develop and commercialize any of our product candidates that are the subject of such licensed rights could be impaired. Additionally, we may be required to reimburse our licensors for all of their expenses related to the prosecution, maintenance, enforcement and defense of patents and patent applications that we in-license from them.
Furthermore, our licensors may have relied on third-party consultants or collaborators or on funds from third parties such that our licensors are not the sole and exclusive owners of the patents we in-licensed. For example, if other third parties have ownership rights to our in-licensed patents, they may be able to license such patents to our competitors, and our competitors could market competing products and technology. This could harm our competitive position, and our business.
Duration of patent terms may be inadequate to protect our competitive position on our product candidates for an adequate amount of time, and the expiration of our patents may subject us to increased competition.*
As of March 31, 2025, the patent portfolio that is assigned to us, jointly owned with others or licensed to us includes issued patents in the United States, Europe, Japan, and other jurisdictions outside the United States, and pending patent applications in the United States, Europe, Japan, and other jurisdictions outside the United States, including issued patents and patent applications related to NKX019 and our NK cell engineering platform. Our portfolio of issued patents, excluding pending patent applications, has estimated expiration dates between 2024 and 2041, subject to any patent terms adjustments or extensions. Our portfolio, including issued patents, and including pending applications, to the extent they issue as patents or are used to establish nonprovisional patent applications that issue as patents, is expected to have estimated expiration dates between 2024 and 2045, subject to any patent terms adjustments or extensions. For instance, composition-of-matter claims in our licensed patent portfolio that relate to our NKSTIM cells are estimated to have expired in Q4 2024, subject to any patent terms adjustments or extensions. We plan to file additional patent applications that could potentially allow for further increase of the exclusive market protection for certain uses of NKX019. However, we can provide no assurance that we will be able to file or receive additional patent protection for these or other product candidates.
Patent expiration dates may be shortened or lengthened by a number of factors, including terminal disclaimers, patent term adjustments, supplemental protection certificates and patent term extensions. Patent term extensions and supplemental protection certificates, and the like, may be impacted by the regulatory process and may not significantly lengthen patent term. Our patent protection could also be reduced or eliminated for noncompliance with various procedural, document submission, fee payment and other requirements imposed by government patent agencies, or by changes in regulations or laws. In addition, if we fail to apply for applicable patent term extensions or adjustments, we will have a more limited time during which we can enforce our granted patent rights.
Given the amount of time required for the development, testing and regulatory review of product candidates, patents protecting such candidates might expire before or shortly after such product candidates are commercialized. We expect to seek extensions of patent terms in the United States and, if available, in other countries where we have or will obtain patent rights. In the United States, the Drug Price Competition and Patent Term Restoration Act of 1984 permits a patent term extension of up to five years beyond the