Image from Dvdgmz - Own work, CC BY-SA 3.0 es, https://commons.wikimedia.org/w/index.php?curid=26231062
In 2006, Rogers Communications of Toronto (Canada's largest cable TV provider) had a million-dollar dispute with phone company Bell Aliant that hinged on the meaning of a single comma.
Bell Aliant had terminated a contract to lease power poles from Rogers. Rogers, however, argued that the contract with Bell Aliant didn't give them that right. The contract language at issue was: "...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 problem was the text between the commas. Bell Aliant argued the second comma had turned that middle section into an interrupting clause that made the one-year notice (mentioned at the end) apply equally to both the initial term and the successive terms. As a result, they argued, they were allowed to opt out of the first term with just a one-year notice.
On the other hand, Rogers had intended that one-year opt-out to apply only to the successive five-year terms -- not the original term.
I side with Bell Aliant on this argument, and so did the original judge, who found they could leave the contract -- and lose Rogers a million dollars in power pole leases.
So, with a million Canadian dollars at stake, Rogers Communications turned to the French version of the contract, the meaning of which was more clearly presented.
The verdict? The judge in the appeal case found for Rogers.
The lesson? Grammar isn't just a fun pastime (well, for ME, at least). It's also what prevents your intention from becoming lost in translation.