Exit watch, week of March 8, 2010

ExactTarget buys Twitter account manager CoTweet

, an Indianapolis-based maker of email marketing software, has acquired CoTweet, provider of a Web-based collaboration platform that allows companies to manage multiple Twitter accounts from a single dashboard. CoTweet has raised a small amount of funding from First Round Capital, Founders Fund and Maples Investments. ExactTarget is also venture-backed, having raised about $155 million in VC funding from Technology Crossover Ventures, Battery Ventures, Insight Venture Partners, Ontagu Newhall and Scale Venture Partners.

Baxter buys ApaTech for $330M

(NYSE: BAX) has agreed to acquire ApaTech, a U.K.-based developer of orthopedic implants. The deal is valued at upwards of $330 million, including an up-front cash payment of $240 million. ApaTech had raised about $70 million in VC funding, with current shareholders including Encore Ventures (via an acquisition of 3i Group’s portfolio) and HealthCor Partners.

SGI scoops up Copan

Silicon Graphics (Nasdaq: SGI) has acquired the assets of Copan Systems, a Longmont, Colo.-based provider of persistent data storage solutions. No financial terms were disclosed. Copan had raised more than $105 million from Austin Ventures, Battery Ventures, Globespan Capital Partners, FirstMark Capital, Westbury Partners and Credit Suisse.

Thermo Fisher completes $145M purchase of Ahura

(NYSE: TMO) has completed its previously-announced acquisition of Ahura Scientific Inc., a Wilmington, Mass.-based developer of optical systems for the detection of unknown and suspect substances. The deal was valued at $145 million in cash, plus an undisclosed amount of earnouts based on 2010 financial milestones. Ahura Scientific had raised nearly $30 million from ARCH Venture Partners, Castile Ventures, Fuse Capital (f.k.a. ComVentures) and GF Private Equity.

Cephalon acquires Ception Therapeutics

(Nasdaq: CEPH) has exercised an option to acquire Ception Therapeutics Inc., a Malvern, Pa.-based drug company whose lead candidates are anti-inflammatory medications. The deal was originally agreed to in early 2008, with Cephalon making a $100 million upfront payment and agreeing to pay another $250 million if it chose to exercise the acquisition option. Ception has raised about $88 million in VC funding from Essex Woodlands Health Ventures, Investor Growth Capital, MDS Life Sciences, New Science Ventures and Aperture Venture Partners.

Solta Medical buys Aesthera

, a publicly listed medical aesthetics company, has acquired Aesthera Corp., a Pleasanton, Calif.-based provider of light-based acne treatments for $6 million in common stock and cash. Aesthera raised about $15 million in venture backing from MedVenture Associates and Adams Street Partners.