HANOI/SINGAPORE, Dec 6 (Reuters) - U.S. private equity firm TA Associates is aiming to sell its minority stake of about 20% in Vietnamese software provider MISA, with a value for the company of more than $500 million, two sources with knowledge of the matter said.

Boston-headquartered TA is working with a financial adviser on the potential divestment although no final decision has been made, the sources said. They declined to be identified as the discussions are private.

TA and MISA did not respond to requests for comment.

Deal activity this year has been robust in Vietnam, one of Asia's fastest-growing economies, making it a bright spot in an otherwise dull Asia-Pacific merger and acquisition market.

LSEG data showed that Asia-Pacific deals volume declined 26% to a decade-low of $546 billion during the first 11 months of 2023.

Hanoi-headquartered MISA, founded in 1994, offers accounting, financial, enterprise resource planning and business management software, with more than 70,000 government sector clients and more than 170,000 enterprise clients, according to its website.

TA announced in 2019 that it had taken a minority stake in MISA but did not disclose financial details of the deal or the exact size of the stake.

TA, founded in 1968, has raised $65 billion in capital to date and focuses on fostering the expansion of companies in technology, healthcare and other sectors, according to its website.

Other recent M&A deals in Vietnam include Bain Capital's investment of $250 million in conglomerate Masan, first announced in October, and Singapore-based Thomson Medical's July deal to acquire Far East Medical Vietnam from healthcare buyout firm Quadria Capital for $381 million. (Reporting by Phuong Nguyen in Hanoi and Yantoultra Ngui in Singapore; Editing by Edmund Klamann)