Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of biopharmaceutical company Theravance (NASDAQ: THRX) climbed as high as 13% today after announcing plans to split into two companies, separating its drugs under development with GlaxoSmithKline from its other operations.

So what: The stock has been stagnant over the past couple of years on sluggish sales and royalties, but the separation should unlock some hidden value from two very different sets of assets. The move also increases the likelihood that Glaxo will eventually buy out Theravance's franchise lung disease drugs Breo and Anoro.

Now what: Theravance expects that the separation will be completed by late 2013 or early 2014. "After the separation, Theravance Biopharma will focus on Theravance's multivalent discovery capabilities and pipeline of programs," wrote the company in a statement. "Royalty Management Co will continue to focus on managing the rights to the significant potential royalty streams from certain products developed under the LABA collaboration with GSK." So while the stock is still too speculative for average Fools, Theravance might be a special situation for biotech-savvy investors to consider.

Interested in more info Theravance? Add it to your watchlist.