Wasserstein & Co. and MidOcean Partners have completed their acquisition of Penton Business Media and closed on the deal that gives MidOcean 50 percent ownership of the new company formed by the merger of Penton and Prism Business Media.

The new company will operate under the Penton brand (unified branding is expected to begin March 15) and be headquartered in New York. The company’s portfolio includes 113 trade magazines, 145 Web sites, 96 industry trade shows and conferences and more than 500 information data products.

Financing sources for the Penton transaction, valued at $530 million, include UBS, J. P. Morgan Securities Inc. and GE Commercial Finance. DeSilva & Phillips and UBS provided financial advisory services to Wasserstein & Co.