A minimum storage regenerating (MSR) subspace family of $ {\mathbb F}_q^{2m} $ is a set $ {\mathcal S} $ of $ m $-spaces in $ {\mathbb F}_q^{2m} $ such that for any $ m $-space $ S $ in $ {\mathcal S} $ there exists an element in $ \mathrm{PGL}(2m, q) $ which maps $ S $ to a complement and fixes $ {\mathcal S} \setminus \{ S \} $ element-wise. We show that an MSR subspace family of $ 2 $-spaces in $ {\mathbb F}_q^4 $ has at most size $ 6 $ with equality if and only if it is a particular subset of a Segre variety. This implies that an $ (k{+}2, k, 4) $-MSR code has $ k \leq 7 $.
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