In a letter dated June 8, 2022 to Kathi Vidal, director of the USPTO, a group of senators led by Patrick Leahy voiced concern over filings of multiple continuation applications, which, according to the letter, result in the formation of "patent thickets" that "stifle competition" and cover a single product or minor variations thereof.

The letter, which can be obtained from Senator Leahy's website at this link, specifically targets the filing of multiple continuations for pharmaceuticals:

In the drug industry, with the most minor, even cosmetic, tweaks to delivery mechanisms, dosages, and formulations, companies are able to obtain dozens or hundreds of patents for a single drug. This practice impedes generic drugs' production, hurts competition, and can even extend exclusivity beyond the congressionally mandated patent term.

Questions are raised about the effectiveness of Terminal Disclaimers and their possible elimination, the high rate of allowances on continuations, which perhaps should be subjected to additional scrutiny, and possible time limits and increased examination fees on the filing of continuations.

Although divisional applications are not mentioned explicitly, and perhaps were excluded deliberately, the letter also states that patent thickets are only "primarily" made up of continuations, perhaps opening the door for future inclusion of divisional applications in their concerns.

The senators asked Director Vidal to issue a Notice of Proposed Rulemaking or a public request for comments, based their questions, by September 1, 2022. It is possible that their letter was prompted from within the USPTO itself, which might already share some of these concerns. Either way, the industry should expect to see something from the USPTO by September.