diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index daa1bc108..54741c1e0 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -1531,7 +1531,7 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
         latest_randao_mixes=[ZERO_HASH for _ in range(LATEST_RANDAO_MIXES_LENGTH)],
         previous_shuffling_start_shard=GENESIS_START_SHARD,
         current_shuffling_start_shard=GENESIS_START_SHARD,
-        previous_shuffling_epoch=GENESIS_EPOCH,
+        previous_shuffling_epoch=GENESIS_EPOCH - 1,
         current_shuffling_epoch=GENESIS_EPOCH,
         previous_shuffling_seed=ZERO_HASH,
         current_shuffling_seed=ZERO_HASH,
@@ -1539,7 +1539,7 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit],
         # Finality
         previous_epoch_attestations=[],
         current_epoch_attestations=[],
-        previous_justified_epoch=GENESIS_EPOCH,
+        previous_justified_epoch=GENESIS_EPOCH - 1,
         current_justified_epoch=GENESIS_EPOCH,
         previous_justified_root=ZERO_HASH,
         current_justified_root=ZERO_HASH,