To solve the equation \( 5^{-5} \cdot 5^{?} = 5^{12} \), we can use the laws of exponents. Specifically, we know that when multiplying powers with the same base, we can add the exponents:
\[ 5^{-5} \cdot 5^{?} = 5^{-5 + ?} \]
Setting this equal to \( 5^{12} \) gives us:
\[ 5^{-5 + ?} = 5^{12} \]
Since the bases are the same, we can set the exponents equal to each other:
\[ -5 + ? = 12 \]
Now, we can solve for \( ? \):
\[ ? = 12 + 5 \]
\[ ? = 17 \]
Thus, the missing value is \( \boxed{17} \).