diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 6bff0f705..2771d19fa 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -522,7 +522,7 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git
     'validator_registry_update_epoch': 'uint64',
 
     # Randomness and committees
-    'latest_randao_mixes': ['bytes32'],
+    'latest_randao_mixes': ['bytes32', LATEST_RANDAO_MIXES_LENGTH],
     'previous_shuffling_start_shard': 'uint64',
     'current_shuffling_start_shard': 'uint64',
     'previous_shuffling_epoch': 'uint64',
@@ -537,10 +537,10 @@ The following data structures are defined as [SimpleSerialize (SSZ)](https://git
     'finalized_epoch': 'uint64',
 
     # Recent state
-    'latest_crosslinks': [Crosslink],
-    'latest_block_roots': ['bytes32'],
-    'latest_active_index_roots': ['bytes32'],
-    'latest_slashed_balances': ['uint64'],  # Balances slashed at every withdrawal period
+    'latest_crosslinks': [Crosslink, SHARD_COUNT],
+    'latest_block_roots': ['bytes32', SLOTS_PER_HISTORICAL_ROOT],
+    'latest_active_index_roots': ['bytes32', LATEST_ACTIVE_INDEX_ROOTS_LENGTH],
+    'latest_slashed_balances': ['uint64', LATEST_SLASHED_EXIT_LENGTH],  # Balances slashed at every withdrawal period
     'latest_attestations': [PendingAttestation],
     'batched_block_roots': ['bytes32'],