A key patent infringement case will be argued April 16 before a full nine-member U.S. Supreme Court after all.

The court announced Wednesday that Justice Samuel Alito Jr., who had recused himself when the court granted review in the case WesternGeco v. ION Geophysical, in January, is “no longer recused.”

Justices usually do not explain their reasons for recusing—or undoing a recusal, for that matter—but the explanation in this case seems relatively clear.

Alito's most recent financial disclosure form indicated he owned $15,000 or less in the stock of Schlumberger Limited. According to the petitioner's brief, filed by Paul Clement of Kirkland & Ellis, WesternGeco is “an indirectly, wholly owned subsidiary” of Schlumberger.

The fact Alito is no longer recused almost certainly means he has sold the stock, thereby erasing the conflict of interest. Alito has “unrecused” at least seven times in the past, according to a search of the court's online docket.

Because of a family inheritance, Alito owns stock in numerous companies, unlike most other justices, and he and his wife have sold some of the holdings over recent years.

Like other justices who own stocks, Alito can also take advantage of a federal law that allows judges to shed stocks to avoid conflicts of interest without incurring capital gains taxes, an exemption that members of Congress also enjoy.

The WesternGeco case is viewed as an important test of whether the court wants to expand the territorial boundaries for imposing damages in patent infringement cases.

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