To stake your claim

Brief Definition: 
Take ownership by putting your name on it.
Further Explanation: 
This idiom comes from early United States' history. During a gold rush or opening of "new" territories, a citizen could run wooden stakes in the ground and everything he found on that land and the land itself would be legally considered his.
Examples: 
John told his roommates to stake their claims on the things in the refrigerator that they wanted to keep because he was cleaning it out today. If not labeled, he was going to throw it out.
Allister complained that every time they have turkey at his house his sister stakes a claim to the wishbone, so Uncle Tom gave it to him this time.
Idiom Ratings
Popularity (Scale 1 to 5): 
3
Formality (Scale 1 to 5): 
5