Geoffrey Tracktenberg reports this comma error which cost one side $1 Million in a legal malpractice case, which stemmed from a contract sentence.  The story itself came from the NY TImes.

"The dispute is over this sentence: "This agreement shall be effective from the date it is made and shall continue in force for a period of five (5) years from the date it is made, and thereafter for successive five (5) year terms, unless and until terminated by one year prior notice in writing by either party."
The regulator concluded that the second comma meant that the part of the sentence describing the one-year notice for cancellation applied to both the five-year term as well as its renewal. Therefore, the regulator found, the phone company could escape the contract after as little as one year."