Insight Partners, a New York-based venture capital and private equity firm, has raised $12.5 billion for its 13th flagship fund — a large sum that was reduced from an even larger target. The fundraising is particularly notable because of the difficult environment for VC firms. “It definitely was the hardest fundraise that I have been involved in at Insight,” said Managing Director Deven Parekh. Initially, the firm had targeted $20 billion for the fund....