So far in 2013, investors have increased stock market positions by $12 billion, according to data from clients, TD Ameritrade CEO Fred Tomczyk said Tuesday.
A number of indicators from TD Ameritrade's client base show that investors have been getting back into equities, loading up on technology and financial stocks, he said.
"So far this year – you may find this number hard to believe – but there have been $12 billion in net buys by our client base," Tomczyk said on CNBC's "Fast Money."
While there has been no "great rotation" from bonds into equities, more fund flows into stocks could be ahead, he added.
"I think you could see people getting their bond fund statements this time for the first time this quarter and where it may be flat to down, and I think that's going to be interesting to see what happens there," Tomczyk said.
The data from TD Ameritrade, he added, came from the company's 5 million retail clients and looking at those who have changed positions within the month, with different financial instruments equalized to level out the positions in options and stocks.
Those, he said, "are the three names that are probably the most prominent."
Trader disclosure: On March 12, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: JOSH BROWN IS LONG LOW; JOSH BROWN IS LONG PFE; JOSH BROWN IS LONG HD; JOSH BROWN IS LONG AAPL; KAREN FINERMAN FL FKL AAPL; KAREN FINERMAN FL KFL BANK OF AMERICA; KAREN FINERMAN FL KFL CITIGROUP; KAREN FINERMAN FL KFL JPMORGAN; KAREN FINERMAN FL WALMART; KAREN FINERMAN FL TGT; KAREN FINERMAN FL KFL MSFT; KAREN FINERMAN FL KFL GOOG; KAREN FINERMAN FL KFL MACY'S; KAREN FINERMAN FL STOCK AND LEAPS GM; KAREN FINERMAN FS LONG PUTS SHORT BONDS JCP; KAREN FINERMAN FS KFS SPX; Guy Adami's wife, Linda, works at Merck; GUY ADAMI OWNS C; GUY ADAMI OWNS GS; GUY ADAMI OWNS INTC; GUY ADAMI OWNS MSFT; GUY ADAMI OWNS AGU; GUY ADAMI OWNS NUE; GUY ADAMI OWNS BTC; DAN NATHAN MS LONG APRIL 22 PUTS; DAN NATHAN BBRY LONG MAR/APR 14 PUT SPREAD; DAN NATHAN TOL LONG APR/JUN 35 PUT SPREAD.