RESTEM, LLC v. JADI CELL, LLC
Before Moore, Schall, and Taranto. Appeal from the Patent Trial and Appeal Board.
Summary: Inherency in product-by-process claims requires the prior art process to inevitably produce the claimed produce, not merely disclose the claimed process steps.
Jadi Cell’s patent covered isolated stem cells produced from mammalian umbilical cord tissue by a process with two key steps: (1) placing the subepithelial layer (SL) of the umbilical cord tissue in direct contact with a growth substrate, and (2) culturing the SL to produce cells with a specific marker expression profile. Restem sought inter partes review. In a final written decision, the Board found that, while the prior art references cited by Restem disclosed similar process steps for culturing umbilical cord-derived stem cells, they did not necessarily result in the claimed product. That is, the prior art processes did not necessarily produce cells with the precise marker expression pattern recited in Jadi Cell’s claims.
Restem appealed, arguing that the prior art inherently anticipated the claims because it used comparable or identical isolation and culturing techniques and therefore would have necessarily produced the recited product. In essence, Restem argued that inherency is automatic for product-by-process claims when the prior art discloses the claimed process steps. However, the Federal Circuit rejected this argument. It explained that inherency in product-by-process claims is not satisfied merely because a prior art process uses similar or even identical steps – the end result must inevitably include the claimed product. The Federal Circuit affirmed the Board’s decision because substantial evidence showed that different culturing conditions and cell-to-cell interactions could influence cell marker expression, meaning the prior art process would not necessarily yield the claimed cell population.
Editor: Sean Murray
