As if awaiting the Supreme Court’s drug preemption ruling in Wyeth v. Levine isn’t enough of a cliffhanger, let’s toss in the Wyeth-Pfizer acquisition for an Indiana Jones-type plot twist.

After Pfizer last month announced its $68 billion acquisition of Wyeth, Wyeth’s counsel in Levine sent the court a letter disclosing the acquisition, just to be on the up-and-up about corporate disclosure. Bottom line: not to worry, the deal is WAY off and we’ll let you know if anything changes.

Except everybody knows that Chief Justice John Roberts owns, or at least used to own, Pfizer stock. You’ll remember that last year, the chief justice’s Pfizer interest resulted in his recusal and a 4-4 split in Warner-Lambert v. Kent, a case dealing with federal preemption and Michigan’s state law preemption of drug liability claims (Pfizer bought Warner-Lambert long ago and inherited the case). The split let stand the Second Circuit’s ruling that Rezulin claims by Michigan residents aren’t preempted and send them back to the Rezulin MDL court. Levine had apparently been “clean” of such conflicts, but then along comes the Pfizer acquisition and we could be back in Kent country.

Of course, Chief Justice Roberts could have since sold his Pfizer stock or put his investments in a blind trust. Or it could be a moot issue, since the acquisition isn’t expected to close before July 31, by which time the court will have ruled in Levine. But it’s not inconceivable that someone could argue that the chief justice’s vote could influence Pfizer or Wyeth’s stock value during the acquisition. It’s all speculation, but as I said in the beginning, it’s a plot twist in a cliffhanger of a case.

This isn’t the first interesting post-argument development in Levine: in December, more than a month after arguments, the court ordered up the trial transcript from the underlying state case, which had resulted in a plaintiff win. One of the attorneys tells me it’s routine when the court is deciding the facts of the case. But I’ve covered other Supreme Court cases and don’t recall the court ordering up more documentation after argument. That could support the view that Levine will be decided more on case-specific facts (did Phenergan’s label specifically warn against IV push administration?) than on the law (federal drug label regulation preempts tort claims based on failure to warn of risks).

The Court returns from recess Feb. 23 and I, for one, can’t wait. Who knows, if there’s another split, we may see “Drug Preemption, Part III.” And by the time another drug preemption case makes it way to arguments, might there be one or two new justices?