diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,10 @@
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## 0.6.7
+### Changed
+- Impose restrictions on recursion for coinbase after height checks.
+
 ## 0.6.6
 ### Added
 - Check whether a transaction can be traced back to a coinbase after certain height.
diff --git a/app/Main.hs b/app/Main.hs
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -289,7 +289,7 @@
             res <-
                 withSnapshot db $ \s -> do
                 let d = (db, defaultReadOptions {useSnapshot = Just s})
-                cbAfterHeight d height txid
+                cbAfterHeight d 100 height txid
             S.json $ object ["result" .= res]
         S.get "/transactions" $ do
             txids <- param "txids"
diff --git a/haskoin-store.cabal b/haskoin-store.cabal
--- a/haskoin-store.cabal
+++ b/haskoin-store.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 44214f2f80c61b6b3d5cdcd27689e23458381088f677d27790d326ea21df2da7
+-- hash: db673c6b1202a70890532986a1332d88c3463356e623cf7e03853a905961700b
 
 name:           haskoin-store
-version:        0.6.6
+version:        0.6.7
 synopsis:       Storage and index for Bitcoin and Bitcoin Cash
 description:    Store blocks, transactions, and balances for Bitcoin or Bitcoin Cash, and make that information via REST API.
 category:       Bitcoin, Finance, Network
diff --git a/src/Haskoin/Store.hs b/src/Haskoin/Store.hs
--- a/src/Haskoin/Store.hs
+++ b/src/Haskoin/Store.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE ConstraintKinds       #-}
 {-# LANGUAGE FlexibleContexts      #-}
+{-# LANGUAGE MultiWayIf #-}
 {-# LANGUAGE GADTs                 #-}
 {-# LANGUAGE LambdaCase            #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
@@ -266,16 +267,31 @@
             {xPubUnspentPath = pathToList p, xPubUnspent = t}
 
 -- | Check if any of the ancestors of this transaction is a coinbase after the
--- specified height.
-cbAfterHeight :: (Monad m, StoreRead i m) => i -> BlockHeight -> TxHash -> m Bool
-cbAfterHeight i h t = fmap (fromMaybe False) . runMaybeT $ do
-    tx <- MaybeT $ getTransaction i t
-    if any isCoinbase (transactionInputs tx)
-       then
-        return $ blockRefHeight (transactionBlock tx) > h
-       else do
-        let ins = nub $ map (outPointHash . inputPoint) (transactionInputs tx)
-        or <$> mapM (lift . cbAfterHeight i h) ins
+-- specified height. Returns 'Nothing' if answer cannot be computed before
+-- hitting limits.
+cbAfterHeight ::
+       (Monad m, StoreRead i m)
+    => i
+    -> Int
+    -> BlockHeight
+    -> TxHash
+    -> m (Maybe Bool)
+cbAfterHeight _ 0 _ _ = return Nothing
+cbAfterHeight i d h t =
+    runMaybeT $ do
+        tx <- MaybeT $ getTransaction i t
+        if any isCoinbase (transactionInputs tx)
+            then return $ blockRefHeight (transactionBlock tx) > h
+            else case transactionBlock tx of
+                     BlockRef {blockRefHeight = b}
+                         | b <= h -> return False
+                     _ -> do
+                         let ins =
+                                 nub $
+                                 map
+                                     (outPointHash . inputPoint)
+                                     (transactionInputs tx)
+                         or <$> mapM (MaybeT . cbAfterHeight i (d - 1) h) ins
 
 -- Snatched from:
 -- https://github.com/cblp/conduit-merge/blob/master/src/Data/Conduit/Merge.hs