A financial analyst said on Tuesday it is likely that a large company may be pushing for a takeover bid for Tasmanian timber company, Gunns.

Media reports have stated that almost 300 million Gunns shares have been traded for the past week, which is equivalent to 37 per cent of the company's issue.

Gunns shares increased at 21 per cent yesterday to 48 cents after speculations amounted that five Chinese paper companies have expressed their interest in buying the Tasmanian forestry company.

Matthew Torenius, a financial analyst said a company may pursue a takeover bid when it has bought at least 20 per cent of another's shares.

"You would have to say that the level of retail interest in the stock so the smaller buyers and sellers really wouldn't add up to the sort of volumes we're seeing," he said.

"So it would suggest that there are some larger parties accumulating a position in Gunns."

The analyst adds that companies should release statements to the stock exchange once they have purchased more than five per cent of Gunns shares.

"I think it's likely that if there is a couple of large buyers in the stock that they've continued to accumulate shares in the company," he said.

Mr. Torenius said identities of bidders may be established within this week once company has successfully took over five per cent shares of Gunns.