GTCR LLC has closed its largest buyout fund yet, after exceeding its fundraising target limit of $4.5 billion.

The private equity firm's GTCR Fund XII secured $5.25 billion of limited partner capital commitments within five months of its launch in May. GTCR's 12th buyout fund will invest in companies operating in business services, technology, media and telecommunications, healthcare and financial services and technology sectors.

The company currently manages approximately $13 billion in AUM.