Mumbai, Dec. 12 :    Mumbai, Dec. 12:  Merrill Lynch, one of the few global financial powerhouses whose opinions sway investors and fund managers alike, has scaled down its recommendation on Infosys Technologies and Wipro - two technology bellwethers that mirror the fortunes of Indian software companies better than any other. While Infosys gets a 'buy' billing, against 'strong buy' earlier, Wipro fetches a 'neutral' grade compared with 'buy'. The revisions have been prompted by a perception that the two stocks have been overbought, leaving them more vulnerable to a wave of profit booking. Infosys' long-term prospects and its attempts to move up the value chain have appreciated and, therefore, its 'buy' recommendation remains. In the case of Wipro, Merrill Lynch blamed its rating revision on the stock's high valuation. It is, however, optimistic about the ADR in the long term, and the efforts made by Wipro to expand its business to other areas such as systems integration and business process outsourcing. The downgrades have come at a time when the two software stocks have felt the heat of profit booking in the past couple of sessions, after weeks of handsome gains. The markets ignored Merrill's change of mind though, with both stocks ending the day significantly higher over their previous close. Broking houses said speculators and a few foreign institutions made brisk purchases in the shares, even as domestic institutions like UTI were seen selling early in the day. The rise in the scrips confounded some analysts, who predicted the possibility of a 'sideways correction' over the next few days.