You must check the box that says you can be claimed as a dependent if you can be claimed, even if you don't want to be claimed and even if the person who could claim you agrees not to.
To see if you can be claimed, you will need to do some math. The key question will be, do you provide more than half your own support. (If you provide less than half, it is not necessary for anyone to prove they pay more than half; only that you pay less than half your own support.)
Support is defined in publication 501 and using worksheet 2 on page 15.
https://www.irs.gov/pub/irs-pdf/p501.pdf
Briefly, support you provide yourself includes:
- money you earn that you spend on your own support -- food, clothing, medical care, housing, tuition, and entertainment.
- Loans you take out in your own name for tuition also count as support you provide to yourself, because you have promised to pay them back.
Money that you spend on someone else's support (such as a partner or child), or money that you save, does not count as support you provide yourself.
Support provided by your parents includes the value of room and board they provide, tuition they pay, medical care they pay for, including insurance premiums, as well as money they provide for food, clothing, computers, cell phone, and so on.
Add up your total support needs, and determine how much of that you pay for.
