Opnet and Riverbed announced a merger on Oct. 29 under which $36.55 in cash and 0.2774 of a Riverbed share would be exchanged for each share of Opnet. The deal terms come to about $41.80 per share for Opnet, which traded Monday, Nov. 5, at roughly $41.92 at a slight premium of 0.3% to their value in the merger.

Riverbed will execute the deal through an exchange offer that it expects can close before the end of the year. Given the need to process the filing through the Securities and Exchange Commission, that timing could be a little aggressive.

Opnet offers network performance management services that are largely complimentary to Riverbed's application performance management markets.

The merger agreement does not include a go-shop for Opnet, which suggests the company had some market check before entering the merger. Also, the founders and top executives at Opnet, Alain and Marc Cohen, are staying with the combined company. The Cohens hold slightly more that 30% of Opnet.

Some arbs might see the apparent speed of executing the deal as a defensive move by Riverbed and an indication that other players in the space such as CA Technologies might be enticed to make a counterbid.

In recent years, practically all software industry deals have traded as if another bidder would surface but few have resulted in bidding wars, an arb said.

The deal seems to have been well received by analysts from a strategic perspective, but Riverbed shares have declined about 16% since the deal was announced, suggesting that the buyer has little room to stretch, which could deflate the prospect of a bidding war even if another party does make a spoiler bid.