Trading resumed today on 33 leveraged ETCs from ETF Securities, according to an announcement from the London Stock Exchange.

Trading in all of the company's 113 portfolios backed by American International Group credit had been suspended on Tuesday as a result of the credit meltdown and the near-bankruptcy of AIG. Even with trading to resume in 33 of the portfolios, the lion's share of the ETF Securities family, 80 commodities portfolios backed by AIG credit, will remain frozen, at least through today. ETF Securities issued a statement saying that it hoped trading would resume on those 80 AIG-backed commodity securities "as soon as possible."

ETF Securities has the largest lineup of exchange-traded commodities in Europe, with $7.65 billion in assets under management as of the beginning of the week, and most, though not all of its portfolios, backed by AIG credit. The credit meltdown has directly influenced the fortunes of ETF Securities and providers of exchange-traded notes (ETNs) as well.

The notes carry credit risk; therefore, if AIG were to go bankrupt, the holders of the unsecured debt notes would become creditors of the firm (see related story).

The portfolios were also plagued by liquidity issues this week as markets for the notes disappeared. There is no fully liquid market for the shares, and earlier in the week, many of the ETCs stopped tracking indexes during trading. The company said earlier this week that it was working on alternate ways to provide investors with liquidity—trying to permit holders of the securities to redeem them directly from the issuer, or trying to arrange suitable collateral to entice market-makers back into the market. 

ETF Securities has two major types of funds that remain unaffected by the credit market fiasco: precious metals funds, which are backed by physical bullion and carry no credit risk; and oil funds, which are backed by Shell Oil.