Services // Legal Opinions

Written legal opinions of patent attorneys are requested in a variety of contexts and for various reasons. In general, an opinion of patent counsel provides a patent attorney's professional opinion and legal analysis concerning whether an invention is patentable, whether a patent is valid or invalid in view of prior, or whether a product or process infringes or does not infringe a patent.

PLP prepares the following types of formal written legal opinions for its clients:

Patentability Opinions

In some circumstances it can be cost-effective to have a patentability search performed on an invention prior to commissioning a patent attorney to prepare and file a patent application in the U.S. Patent & Trademark Office (USPTO) claiming the invention. PLP routinely performs these types of patentability searches for its clients. (See Patentability Searches in the description of our Patent Preparation and Prosecution practice.)

Based on the results of a patentability search, we prepare and provide the firm's professional written opinion as to whether the USPTO would deem the invention to be patentable. The client can then use the opinion to decide whether to proceed with having a patent application prepared and submitting to the USPTO, or take steps to improve the invention so that it would more likely be deemed patentable.

Validity and Infringement Opinions

Validity and infringement opinions are requested by those concerned with possibly infringing patents of others. They are also requested by patentees.

Those Concerned with Infringing Patents of Others

Those who know that they might be possibly infringing the patent of another have a duty to exercise due care and determine whether there is infringement. Failing to heed this duty can result in a court concluding that the infringement was willful and awarding the patentee treble damages.

The best way to gauge whether patent infringement is occurring and protect against willful infringement is to contact a patent attorney as soon as possible after becoming aware of any possibly infringing activity. Often, the patent attorney will be able to provide a favorable opinion that infringement is lacking or that the patent is invalid and unenforceable in view of prior art.

Although there is no affirmative duty to seek a legal opinion from patent counsel regarding the possiblity of infringement, if the patent is ever asserted in a patent infringement lawsuit, the opinion can be produced and relied on by the accused infringer to support a defense against infringement. It can also be used to help demonstrate to the court that due care was exercised in avoiding willfully infringing the patent and thereby reduce the likelihood that the court will award treble damages.


Patentees also request validity and infringement opinions of their own patents. For example, prior to initiating licensing negotiations or patent infringement lawsuits, well-advised patentees seek validity and/or infringement opintions from patent counsel to verify and fortify their validity and infringement positions. If a patent litigation lawsuit is required to stop an infringer, the patentee can further use the written opinion to demonstrate that it acted in good faith prior to commencing the lawsuit.

Patentees having patent enforcement insurance (i.e., infringement abatement insurance) are also often required to seek and provide favorable validity and/or infringement opinions to their insurer as a condition to invoking the insurance.

Freedom-to-Operate Opinions

Often times, a company needs a legal opinion from a patent attorney concerning whether a new product or process might possibly infringe ANY patents, including patents not even known to the company. These types of legal opinions are known as "freedom-to-operate," "clearance," or "right-to-use" opinions.

Venture capitalists and companies considering acquiring the assets of target companies also request freedom-to-operate opinions to determine whether a target company's products and processes infringe patents of others and to identify problem patents adversely affecting the valuation of the target company.

Freedom-to-operate opinions can have a significant impact on the founding or business course of a company and contain information that can spare investors and companies a tremendous amount of legal complications. For example, they often contain information critical to determining whether to halt development of a new product or whether to proceed with acquiring assets of a target company. Often, they also contain important information suggesting ways to design around claims of problem patents and identifify patents for which validity opinions should be requested.

Back to Top