Google can not provide you with tax advice.
Any advice received in this document, on IRC, or on any mailing list does not constitute professional advice.
It is your responsibility to consult with a tax professional if you have questions about how any money received from Google Summer of Code will impact you.
If you are a student studying abroad, your International Student Affairs Office (or equivalent) may be able to help you with further information or a referral to a tax professional.
Depending on your tax residency and location(s) where you perform work, you may be required to pay taxes in more than one country.