New York Attorney General Eliot Spitzer rocked the mutual fund world this fall with the revelation that four fund firms allowed hedge fund Canary Capital Partners to engage in abusive trading within their funds. Now there may be at least one more firm to add to the Canary list. Van Eck Funds, a New York-based firm that manages $1.3 billion in mutual funds and hedge funds with mostly a global focus, has been subpoenaed by Spitzer's office as part of the ongoing investigation into improper trading within mutual funds, an individual familiar with the matter said. At issue: concern that Van Eck allowed Canary to make improper trades within several of its funds, said individuals close to the situation. TheStreet.com made repeated attempts to contact Van Eck regarding the Spitzer investigation, its potential relationship with Canary as well as suspiciously high levels of trading activity detected within some of its funds. The firm didn't respond. A spokeswoman for Spitzer's office declined to comment on the investigation, but an individual familiar with the matter said Van Eck was subpoenaed sometime after Sept. 3, the date when Spitzer first announced the problems with abusive trading practices at Canary. According to another individual familiar with the matter, Van Eck and Canary established contact with each other regarding trading arrangements at least two years ago. Another person familiar with the situation said Canary was allowed to improperly trade certain Van Eck funds. The nature and scope of Spitzer's investigation into Van Eck isn't immediately clear -- an individual familiar with Spitzer's office indicated the investigation into any link between Van Eck and Canary wasn't as far along as investigations into other fund firms. However, several funds within the firm had suspiciously high levels of trading activity over the past two years. International funds, such as the offerings from Van Eck, have attracted hedge funds and other entities eager to take advantage of inefficiencies in global investing and mutual fund prices -- specifically via "time-zone arbitrage." With time-zone arbitrage, investors aim to take advantage of "stale prices" in a fund's net asset value due to the fact that markets close at different time around the globe. For instance, if the U.S. markets have a big rally one day, the overseas markets are closed -- but they are certain to get a big pop because they often take their cue from U.S. markets. Time-zone arbitrageurs buy the international fund before the market opens, get the almost-guaranteed profit, and sell quickly -- typically within 24 hours.