News of Sony's acquisition comes three months after Hipgnosis rebranded itself as Recognition Music Group.
The new name brings three previously separate Hipgnosis companies — both catalog acquisition funds and their investment manager — under one management team.
A pair of lawsuits over $1.5 million in unpaid bonuses provide a look into the kinds of contracts that Hipgnosis entered into during its acquisition spree.
With 99.97% of shares voted voting for its $1.6 billion offer, Blackstone now owns 100% of the company that popularized music as an asset class
The company's founder calls it the "right time" to "undertake a strategic shift of focus."
The private equity giant is sticking to its offer of $1.31 per share, which values Hipgnosis Songs Fund's share capital at $1.584 billion.
Concord said on Thursday it would not raise its bid to beat Blackstone's $1.6 billion offer for the publicly listed music royalty fund.
Concord's offer of $1.25 per share has been rejected, with HSF directors now recommending shareholders go with Blackstone.
HSF shares have recently been trading above the latest offer prices, suggesting some investors expect the bidding to continue.
The Nashville-based company is now offering $1.25 per share, a penny more than Blackstone's possible bid, and says it wants to sell 30% of the fund's assets.
