Vista Equity Partners LLC’s talks to merge three of its companies with Apollo Strategic Growth Capital (NYSE:APSG) in a $15 billion transaction have been halted, according to people familiar with the matter. Discussions about a merger featuring Vista’s Solera Holdings, Inc., DealerSocket Inc. and Omnitracs, LLC stalled in recent days amid weak market conditions for technology companies, said some of the people, who asked not to be named because the information isn’t public. It isn’t clear when or if talks will be revived. Bloomberg reported the expanded deal involving the trio of technology companies that service the auto industry earlier this month. An Apollo representative declined to comment. A Vista spokesperson didn’t immediately respond to a request for comment.