Arbitrage

For those who are unaware, arbitrage is a key concept that makes sure that securities are properly priced in a market. I was reading the wallstreetjournal a while ago and i remembered that Countrywide Financial was supposed to be bought by Bank of America with a share swap of 0.1822. Curious as to whether the arbitrage would price the two securities properly, i did some research online. Countrywide Financial ceased to be independent on 30/06/2008 at a price of 4.25. At a share swap of 0.1822, it was priced at around 23.32 per Bank of America share. The ending price of Bank of America for the same day was 23.87 (according to Bigcharts.com.) The slight difference in prices is due to transaction fees, commissions fees are other miscellaneous stuff. I would say that arbitrage did a pretty decent job.