SHANGHAI (Reuters) - Alibaba ( BABA ) co-founder Jack Ma has penned a rare lengthy memo to employees that expresses support for the internet giant's restructuring efforts, a sign that he may be willing to take a more active role after spending the last few years out of the spotlight.

Alibaba's ( BABA ) Hong Kong-listed shares surged 5.5% in morning trade after the post, on course for their biggest one-day percentage gain since Feb. 6.

In the post, which was roughly a page long, Ma praised the leadership of CEO Eddie Wu and chairman Joe Tsai and said the company's split into six divisions a year ago had helped streamline decision-making, making Alibaba ( BABA ) more agile and customer-focused.

Ma, China's best-known tech entrepreneur, publicly criticised Chinese regulators in a speech in October 2020, derailing a massive listing by fintech company Ant Group, which he also founded. That was followed by regulatory crackdowns on the Chinese tech sector with Ma largely withdrawing from public life.

"Our innovation has never been to surpass our opponents, but to catch up to the future," he wrote in the post. "Innovation is not about following the trend, it's a test of your true ability to survive."