Morgan Stanley emerges as big KPN investor AMSTERDAM (Reuters) - Morgan Stanley (MS.N) has emerged as one of the biggest shareholders in KPN (KPN.AS), the Dutch telecoms group which Mexican billionaire Carlos Slim has set his sights on as a stepping stone into Europe. A filing with Dutch financial market regulator AFM shows that Morgan Stanley has the equivalent of 10.01 percent in KPN. Morgan Stanley's change in ownership was registered with AFM on May 4 - just a few days before Slim's America Movil (AMXL.MX) said on May 7 that it wants to buy up to 28 percent of the Dutch telecoms firm. KPN said on Tuesday that the unsolicited tender offer from America Movil to pay 8 euros per share to build up a 28 percent stake undervalued its business. It has hired Goldman Sachs and JP Morgan to help it weigh its "strategic option." America Movil said it currently owns about 4.8 percent of KPN after buying shares in the open market. Capital Research and Management Company, part of The Capital Group Companies, is the biggest investor in KPN, according to Reuters data. It lifted its interest to 15.1 percent from 10.1 percent, according to AFM filings in January, giving it 15.1 percent of the voting rights in KPN. The Capital Group Companies, based in the United States, is a group of investment management firms. Morgan Stanley had a direct capital stake of 4.93 percent, and owned the remaining 5.08 percent in futures, options and swaps, the regulatory filing with the AFM showed. It did not own an interest in KPN - either via shares, options, American depository receipts, or swaps - that in total amounted to 5 percent or more before the filing was made on May 4. Reporting by Sara Webb and Gilbert Kreijger