Billable hours be damned: This trial is on!

Yesterday, lawyers for GlaxoSmithKline (NYSE: GSK) made opening statements in its lawsuit against competitor Abbott Labs (NYSE: ABT). Glaxo and its co-plaintiffs, Rite Aid (NYSE: RAD) and CVS Caremark (NYSE: CVS), have alleged damages of $1.5 billion and are seeking triple damages of $4.5 billion in the case.

With the suit originally filed in late 2007, this day has been a long time coming. The brouhaha stems from a dramatic 400% price increase of Abbott's Norvir back in 2003. Norvir is an important component in the "drug cocktails" that patients use to treat HIV infections. Sky-high price hikes caused outrage among those with AIDS and HIV, as well as competing drug firms that sold combo treatments boosted by Norvir. And even though raising prices is not illegal in itself, where Abbott allegedly ran into trouble was in failing to raise the price of its protease inhibitor Kaletra, which also uses Norvir as a boosting agent. That allowed Kaletra to undercut its rivals' offerings.

Glaxo alleges that Abbott tried to create a monopoly, and claims that sales of its HIV medicine Lexiva fell by 50% because of the Norvir price increase. After the hike, Lexiva costs users 75% more per day than Kaletra. Pardon the pun, but that's a tough pill to swallow.

For its part, Abbott maintains that the Norvir price hike was a "legitimate response to advances Abbott scientists made" and represented "fair value" for the drug. Furthermore, Abbott insists that despite annual sales of more than $1 billion, Kaletra's 30% market share didn't constitute a monopoly.

The good news is that after the long wait, the trial is expected to last only three weeks, and a decision should follow soon afterward. Nevertheless, investors should anticipate an appeal regardless of the outcome. Cases involving multibillion-dollar verdicts inevitably go several rounds, so it will be a while until we get a definitive resolution.

A full $4.5 billion judgment would represent 6% of Abbott's market cap, but even if the company has to pay the entire amount out of its own pocket, Abbott has more than enough cash on hand to pay it. The greater concern for shareholders would be the long-term sales impact that lower pricing and fiercer competition would bring. However, for Glaxo, pharmacies, and the people who depend on this medication, lower costs and more choice would be an ideal outcome.

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David Williamson own no shares of the companies mentioned. The Fool owns shares of GlaxoSmithKline, which is a Motley Fool Global Gains recommendation. Motley Fool Alpha owns shares of Abbott Laboratories. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.