I had a limit order with OH selling a short vertical put spread on GE 25/27.5 for 50 cents. The 25 b/a was .12/.13 (going long) and the 27.5 b/a was .53/.54 (going short) for at least 10 seconds. This order did not execute any contracts. The response OH had was that it could have been cross-market quoting. I'm curious if this order would have executed with another broker. To me this is similar to a market order (put on for 10 seconds) not executing. In the past, Scott Sheridan from TOS said they would not match OH commisions because "they internalize their flow, don't have live quotes or charts and pass on exchange fees." Would the above order have executed on TOS? What does internalizing their flow mean? Thanks!