New Zealand's market regulator has written to Ross Asset Management investors trying to get information to help its probe of the collapsed Wellington firm.
The Financial Markets Authority on Friday sent out a letter and a 16-page questionnaire to those who had money with RAM.
"Substantial enquiries have already been conducted by the investigation team, and the further information sought here is very important to our investigation," the FMA's Jason Lunjevich said in the letter.
The authority is looking for information specifically from those who still had money with RAM last September, around a month before the firm and the home of its founder, David Ross, were raided by the FMA.
Ross was still winning over clients at this time and some investors were even considering giving him more money.