An engagement to marry two longtime U.S.-based BPO firms could be held up if not broken up on the altar by threatened legal wrangling.

NCO Group, through its majority owner One Equity Partners (OEP), will obtain APAC Customer Services for $470 million in an all cash-deal. OEP will combine APAC with NCO Group to, says APAC’s press release “build market leadership in business process outsourcing and customer care solutions.”

The acquisition announced July 7 by OEP, which is JP Morgan (News - Alert) Chase’s the private investment arm, would net APAC shareholders $8.55 per share, which is approximately a $57 million premium over APAC's closing share price on July 6, 2011.

APAC's Board of Directors has unanimously approved the transaction that is expected to close in fourth quarter 2011. APAC chair Theodore G. Schwartz and his affiliated entities, representing approximately 39 percent of APAC's outstanding shares, have agreed to vote in favor of the sale.

"We believe that this transaction represents compelling value, and the Board is pleased to recommend this deal to APAC's shareholders,” stated Schwartz.

“APAC has a market-leading reputation for delivering exceptional customer experiences,” said Tom Kichler, Managing Director at One Equity Partners “We believe this combination will allow both APAC and NCO to enhance the levels of service and support that they currently provide to their valued customers. We are excited about investing behind the growth of these two great businesses.”

Wall Street seems to agree, so far. At presstime, APAC shares climbed to $8.44 today, a 55 percent jump over Wednesday’s close at $5.44.

The Street reports that trading volume is at 16.3 million, 107.2 times the daily average of 151,600.

“APAC Customer Services has a market cap of $272 million and is part of the services sector and diversified services industry. Shares are down 10.4% year to date as of the close of trading on Wednesday.”

“TheStreet Ratings rates APAC Customer Services as a buy. The company's strengths can be seen in multiple areas, such as its revenue growth, attractive valuation levels, growth in earnings per share, increase in net income and notable return on equity. We feel these strengths outweigh the fact that the company shows weak operating cash flow. “

So are APAC’s shareholders getting their fair share from the sale to OEP? Two law firms, Brower Piven and Tripp Levy have announced investigations into the deal for that reason.

Brower Piven announced: “that it has commenced an investigation into possible breaches of fiduciary duty to current shareholders of APAC Customer Services, Inc. and other violations of state law by the board of directors of APAC relating to the proposed acquisition of the company. The firm's investigation seeks to determine, among other things, whether the board breached their fiduciary duties by failing to maximize shareholder value.”

Tripp Levy in its announcement said: “The investigation concerns, among other things, whether the consideration to be paid to APAC shareholders is unfair, inadequate, and substantially below the fair or inherent value of APAC. Indeed, analysts have projected that APAC's true going forward value is at least $9 per share. The investigation further concerns whether the board of directors of APAC may have breached their fiduciary duties by not acting in APAC shareholders' best interests in connection with the sale process of APAC. “