diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3919472..9452098 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,6 +17,7 @@ jobs:
       - name: Setup Rust
         uses: dtolnay/rust-toolchain@stable
         with:
+          toolchain: stable
           components: rustfmt, clippy
 
       - name: Format check
diff --git a/creator-keys/tests/creator_fee_rotation_regression.rs b/creator-keys/tests/creator_fee_rotation_regression.rs
new file mode 100644
index 0000000..1430544
--- /dev/null
+++ b/creator-keys/tests/creator_fee_rotation_regression.rs
@@ -0,0 +1,65 @@
+//! Regression test verifying creator fee recipient updates correctly after rotation.
+
+mod contract_test_env;
+
+use contract_test_env::{register_creator_keys, set_pricing_and_fees, test_env_with_auths};
+use creator_keys::RegisterCreatorParams;
+use soroban_sdk::{testutils::Address as _, Address, String};
+
+#[test]
+fn test_creator_fee_recipient_rotation_regression() {
+    let env = test_env_with_auths();
+    let (client, _) = register_creator_keys(&env);
+    set_pricing_and_fees(&env, &client, 1000, 9000, 1000);
+
+    let creator = Address::generate(&env);
+    client.register_creator(
+        &RegisterCreatorParams {
+            creator: creator.clone(),
+            handle: String::from_str(&env, "alice"),
+        },
+        &None,
+        &None,
+        &None,
+        &None,
+        &None,
+    );
+
+    // Initial fee recipient is the creator themselves
+    assert_eq!(client.get_creator_fee_recipient(&creator), creator);
+
+    // Set custom initial fee recipient
+    let initial_recipient = Address::generate(&env);
+    client.update_creator_fee_recipient(&creator, &initial_recipient);
+
+    let buyer = Address::generate(&env);
+    let quote1 = client.get_buy_quote(&creator);
+
+    // Execute buy 1
+    client.buy_key(&creator, &buyer, &quote1.total_amount, &None);
+
+    // Initial recipient received the fee (tracked under creator's fee balance)
+    let balance_after_buy1 = client.get_creator_fee_balance(&creator);
+    assert_eq!(balance_after_buy1, quote1.creator_fee);
+
+    // Rotate the creator fee recipient to a new address
+    let new_recipient = Address::generate(&env);
+    client.update_creator_fee_recipient(&creator, &new_recipient);
+
+    // New recipient is set correctly
+    assert_eq!(client.get_creator_fee_recipient(&creator), new_recipient);
+
+    // Execute buy 2
+    let quote2 = client.get_buy_quote(&creator);
+    client.buy_key(&creator, &buyer, &quote2.total_amount, &None);
+
+    // New recipient receives fee after rotation (tracked under creator's fee balance)
+    let balance_after_buy2 = client.get_creator_fee_balance(&creator);
+    assert_eq!(balance_after_buy2 - balance_after_buy1, quote2.creator_fee);
+
+    // Since the old recipient is no longer the fee recipient, they receive nothing from subsequent trades.
+    assert_ne!(
+        client.get_creator_fee_recipient(&creator),
+        initial_recipient
+    );
+}
diff --git a/creator-keys/tests/dividend_events.rs b/creator-keys/tests/dividend_events.rs
index 367d9d9..ece1083 100644
--- a/creator-keys/tests/dividend_events.rs
+++ b/creator-keys/tests/dividend_events.rs
@@ -10,6 +10,7 @@ use creator_keys::events::{
     dividend_claimed_topics, dividend_distributed_topics, DividendClaimedEvent,
     DividendDistributedEvent,
 };
+use soroban_sdk::testutils::Ledger;
 use soroban_sdk::{testutils::Address as _, testutils::Events, Address, IntoVal};
 
 #[test]
@@ -89,3 +90,54 @@ fn test_claim_dividend_event_topics_and_payload() {
     assert_eq!(event.claimant, buyer);
     assert_eq!(event.amount, claimed);
 }
+
+#[test]
+fn test_distribute_dividend_event_fields_individual_assertions() {
+    let env = test_env_with_auths();
+    let (client, _) = register_creator_keys(&env);
+    // Set pricing and fees with 10% protocol fee
+    set_pricing_and_fees(&env, &client, 100, 9000, 1000);
+    let creator = register_test_creator(&env, &client, "alice");
+    let buyer = Address::generate(&env);
+
+    // Distribute to a creator with a known supply (e.g. 2 keys bought)
+    client.buy_key(&creator, &buyer, &100, &None);
+    client.buy_key(&creator, &buyer, &100, &None);
+
+    // Set env ledger to a positive non-zero sequence
+    let mut ledger_info = env.ledger().get();
+    ledger_info.sequence_number = 12345;
+    env.ledger().set(ledger_info);
+
+    let distributor = Address::generate(&env);
+    let gross_amount = 20_000i128;
+    distribute_test_dividend(&client, &creator, &distributor, gross_amount);
+
+    let events = env.events().all();
+    let (_, data) = events
+        .iter()
+        .rev()
+        .find_map(|(_, topics, data)| {
+            if topics == dividend_distributed_topics(&creator).into_val(&env) {
+                Some((topics, data))
+            } else {
+                None
+            }
+        })
+        .expect("DividendDistributed event not found");
+
+    let event: DividendDistributedEvent = data.into_val(&env);
+
+    // Assert creator matches the creator used
+    assert_eq!(event.creator, creator);
+
+    // Assert total_amount reflects the gross amount before protocol fee deduction (not the net amount)
+    assert_eq!(event.total_amount, gross_amount);
+
+    // Assert snapshot_supply matches total supply at distribution time
+    assert_eq!(event.snapshot_supply, 2);
+
+    // Assert ledger is a positive non-zero value
+    assert!(event.ledger > 0);
+    assert_eq!(event.ledger, 12345);
+}
diff --git a/creator-keys/tests/locked_allocation_claimed_view_regression.rs b/creator-keys/tests/locked_allocation_claimed_view_regression.rs
new file mode 100644
index 0000000..161fcf1
--- /dev/null
+++ b/creator-keys/tests/locked_allocation_claimed_view_regression.rs
@@ -0,0 +1,64 @@
+//! Regression test verifying `get_locked_allocation` returns claimed `true` after claim.
+
+mod contract_test_env;
+
+use contract_test_env::{register_creator_keys, test_env_with_auths};
+use creator_keys::LockedAllocation;
+use soroban_sdk::testutils::{Address as _, Ledger};
+use soroban_sdk::{Address, String};
+
+#[test]
+fn test_get_locked_allocation_returns_claimed_true_after_claim() {
+    let env = test_env_with_auths();
+    let (client, _) = register_creator_keys(&env);
+
+    let creator = Address::generate(&env);
+    let handle = String::from_str(&env, "alice");
+    let unlock_ledger: u32 = 1000;
+    let amount: u32 = 50;
+
+    let mut ledger_info = env.ledger().get();
+    ledger_info.sequence_number = 1;
+    env.ledger().set(ledger_info.clone());
+
+    client.register_creator(
+        &creator,
+        &handle,
+        &Some(LockedAllocation {
+            amount,
+            unlock_ledger,
+            claimed: false,
+        }),
+        &None,
+        &None,
+        &None,
+    );
+
+    // Assert claimed field is false before claim
+    let alloc_before = client.get_locked_allocation(&creator).unwrap();
+    assert!(
+        !alloc_before.claimed,
+        "claimed field must be false before claim"
+    );
+
+    // Advance to exactly unlock_ledger.
+    ledger_info.sequence_number = unlock_ledger;
+    env.ledger().set(ledger_info);
+
+    // Claim the allocation
+    client.claim_locked_allocation(&creator);
+
+    // Call get_locked_allocation and assert claimed is true
+    let alloc_after1 = client.get_locked_allocation(&creator).unwrap();
+    assert!(
+        alloc_after1.claimed,
+        "claimed field must be true after successful claim"
+    );
+
+    // Call again and assert it is still true
+    let alloc_after2 = client.get_locked_allocation(&creator).unwrap();
+    assert!(
+        alloc_after2.claimed,
+        "claimed field must remain true on subsequent reads"
+    );
+}
diff --git a/creator-keys/tests/quadratic_curve_symmetry_regression.rs b/creator-keys/tests/quadratic_curve_symmetry_regression.rs
new file mode 100644
index 0000000..208208a
--- /dev/null
+++ b/creator-keys/tests/quadratic_curve_symmetry_regression.rs
@@ -0,0 +1,110 @@
+//! Regression test verifying buy and sell quote symmetry for the Quadratic preset.
+//!
+//! The cost (price/fees) to buy N keys at supply S must equal the proceeds (price/fees)
+//! from selling N keys at supply S+N.
+
+mod contract_test_env;
+
+use contract_test_env::{
+    register_creator_keys, set_curve_slope, set_pricing_and_fees, test_env_with_auths,
+};
+use creator_keys::CurvePreset;
+use soroban_sdk::{testutils::Address as _, Address, String};
+
+const KEY_PRICE: i128 = 1000;
+const CREATOR_BPS: u32 = 9000;
+const PROTOCOL_BPS: u32 = 1000;
+const QUADRATIC_SLOPE: i128 = 10;
+
+fn assert_symmetry_for_params(
+    client: &creator_keys::CreatorKeysContractClient<'_>,
+    creator: &Address,
+    buyer: &Address,
+    start_supply: u32,
+    n: u32,
+) {
+    // 1. Advance supply to start_supply
+    let current_supply = client.get_total_key_supply(creator);
+    if current_supply < start_supply {
+        for _ in current_supply..start_supply {
+            let quote = client.get_buy_quote(creator);
+            client.buy_key(creator, buyer, &quote.total_amount, &None);
+        }
+    }
+
+    assert_eq!(client.get_total_key_supply(creator), start_supply);
+
+    // 2. Accumulate buy quotes for N keys and execute buys
+    let mut total_buy_price = 0;
+    let mut total_buy_creator_fee = 0;
+    let mut total_buy_protocol_fee = 0;
+
+    for _ in 0..n {
+        let quote = client.get_buy_quote(creator);
+        total_buy_price += quote.price;
+        total_buy_creator_fee += quote.creator_fee;
+        total_buy_protocol_fee += quote.protocol_fee;
+        client.buy_key(creator, buyer, &quote.total_amount, &None);
+    }
+
+    assert_eq!(client.get_total_key_supply(creator), start_supply + n);
+
+    // 3. Accumulate sell quotes for N keys and execute sells
+    let mut total_sell_price = 0;
+    let mut total_sell_creator_fee = 0;
+    let mut total_sell_protocol_fee = 0;
+
+    for _ in 0..n {
+        let quote = client.get_sell_quote(creator, buyer);
+        total_sell_price += quote.price;
+        total_sell_creator_fee += quote.creator_fee;
+        total_sell_protocol_fee += quote.protocol_fee;
+        client.sell_key(creator, buyer, &None);
+    }
+
+    assert_eq!(client.get_total_key_supply(creator), start_supply);
+
+    // 4. Assert symmetry
+    assert_eq!(
+        total_buy_price, total_sell_price,
+        "Price asymmetry at supply {} for N {}",
+        start_supply, n
+    );
+    assert_eq!(
+        total_buy_creator_fee, total_sell_creator_fee,
+        "Creator fee asymmetry at supply {} for N {}",
+        start_supply, n
+    );
+    assert_eq!(
+        total_buy_protocol_fee, total_sell_protocol_fee,
+        "Protocol fee asymmetry at supply {} for N {}",
+        start_supply, n
+    );
+}
+
+#[test]
+fn test_quadratic_curve_symmetry() {
+    let env = test_env_with_auths();
+    let (client, _) = register_creator_keys(&env);
+    set_pricing_and_fees(&env, &client, KEY_PRICE, CREATOR_BPS, PROTOCOL_BPS);
+    set_curve_slope(&env, &client, QUADRATIC_SLOPE);
+
+    let creator = Address::generate(&env);
+    client.register_creator(
+        &creator,
+        &String::from_str(&env, "quadcreator"),
+        &None,
+        &None,
+        &Some(CurvePreset::Quadratic),
+        &None,
+    );
+
+    let buyer = Address::generate(&env);
+
+    // Cover supply levels: 0, 50, and 500
+    // Cover both small and large key amounts
+    assert_symmetry_for_params(&client, &creator, &buyer, 0, 1);
+    assert_symmetry_for_params(&client, &creator, &buyer, 0, 10);
+    assert_symmetry_for_params(&client, &creator, &buyer, 50, 5);
+    assert_symmetry_for_params(&client, &creator, &buyer, 500, 50);
+}