No, you can only say no thanks and leave. I strongly suggest to anyone who gets hired at Google to read the employment contract completely (you can ask them to send it to you before you start). If you have a friend who understands contract law, have them explain it to you. Then decide.

Unlike in credit situations there is no equivalent of the Fair Credit Act covering employment contracts. Many employers exploit that by writing some very crafty wording which reads one way but on close inspection says the opposite.