diff --git a/stores/metadata_test.go b/stores/metadata_test.go
index 205812287..b39816c1f 100644
--- a/stores/metadata_test.go
+++ b/stores/metadata_test.go
@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"os"
 	"reflect"
-	"sort"
 	"strings"
 	"testing"
 	"time"
@@ -4308,99 +4307,3 @@ func TestUpdateObjectReuseSlab(t *testing.T) {
 		}
 	}
 }
-
-func TestTypeCurrency(t *testing.T) {
-	ss := newTestSQLStore(t, defaultTestSQLStoreConfig)
-	defer ss.Close()
-
-	// prepare the table
-	if isSQLite(ss.db) {
-		if err := ss.db.Exec("CREATE TABLE currencies (id INTEGER PRIMARY KEY AUTOINCREMENT,c BLOB);").Error; err != nil {
-			t.Fatal(err)
-		}
-	} else {
-		if err := ss.db.Exec("CREATE TABLE currencies (id INT AUTO_INCREMENT PRIMARY KEY, c BLOB);").Error; err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	// insert currencies in random order
-	if err := ss.db.Exec("INSERT INTO currencies (c) VALUES (?),(?),(?);", bCurrency(types.MaxCurrency), bCurrency(types.NewCurrency64(1)), bCurrency(types.ZeroCurrency)).Error; err != nil {
-		t.Fatal(err)
-	}
-
-	// fetch currencies and assert they're sorted
-	var currencies []bCurrency
-	if err := ss.db.Raw(`SELECT c FROM currencies ORDER BY c ASC`).Scan(&currencies).Error; err != nil {
-		t.Fatal(err)
-	} else if !sort.SliceIsSorted(currencies, func(i, j int) bool {
-		return types.Currency(currencies[i]).Cmp(types.Currency(currencies[j])) < 0
-	}) {
-		t.Fatal("currencies not sorted", currencies)
-	}
-
-	// convenience variables
-	c0 := currencies[0]
-	c1 := currencies[1]
-	cM := currencies[2]
-
-	tests := []struct {
-		a   bCurrency
-		b   bCurrency
-		cmp string
-	}{
-		{
-			a:   c0,
-			b:   c1,
-			cmp: "<",
-		},
-		{
-			a:   c1,
-			b:   c0,
-			cmp: ">",
-		},
-		{
-			a:   c0,
-			b:   c1,
-			cmp: "!=",
-		},
-		{
-			a:   c1,
-			b:   c1,
-			cmp: "=",
-		},
-		{
-			a:   c0,
-			b:   cM,
-			cmp: "<",
-		},
-		{
-			a:   cM,
-			b:   c0,
-			cmp: ">",
-		},
-		{
-			a:   cM,
-			b:   cM,
-			cmp: "=",
-		},
-	}
-	for i, test := range tests {
-		var result bool
-		query := fmt.Sprintf("SELECT ? %s ?", test.cmp)
-		if !isSQLite(ss.db) {
-			query = strings.Replace(query, "?", "HEX(?)", -1)
-		}
-		if err := ss.db.Raw(query, test.a, test.b).Scan(&result).Error; err != nil {
-			t.Fatal(err)
-		} else if !result {
-			t.Errorf("unexpected result in case %d/%d: expected %v %s %v to be true", i+1, len(tests), types.Currency(test.a).String(), test.cmp, types.Currency(test.b).String())
-		} else if test.cmp == "<" && types.Currency(test.a).Cmp(types.Currency(test.b)) >= 0 {
-			t.Fatal("invalid result")
-		} else if test.cmp == ">" && types.Currency(test.a).Cmp(types.Currency(test.b)) <= 0 {
-			t.Fatal("invalid result")
-		} else if test.cmp == "=" && types.Currency(test.a).Cmp(types.Currency(test.b)) != 0 {
-			t.Fatal("invalid result")
-		}
-	}
-}
diff --git a/stores/types.go b/stores/types.go
index 42a8d29e4..6b14027b9 100644
--- a/stores/types.go
+++ b/stores/types.go
@@ -17,6 +17,7 @@ import (
 )
 
 const (
+	proofHashSize = 32
 	secretKeySize = 32
 )
 
@@ -35,6 +36,10 @@ type (
 	balance        big.Int
 	unsigned64     uint64 // used for storing large uint64 values in sqlite
 	secretKey      []byte
+
+	// NOTE: we have to wrap the proof here because Gorm can't scan bytes into
+	// multiple slices, all bytes are scanned into the first row
+	merkleProof struct{ proof []types.Hash256 }
 )
 
 // GormDataType implements gorm.GormDataTypeInterface.
@@ -341,6 +346,7 @@ func (u unsigned64) Value() (driver.Value, error) {
 	return int64(u), nil
 }
 
+// GormDataType implements gorm.GormDataTypeInterface.
 func (bCurrency) GormDataType() string {
 	return "bytes"
 }
@@ -366,3 +372,36 @@ func (sc bCurrency) Value() (driver.Value, error) {
 	binary.BigEndian.PutUint64(buf[8:], sc.Lo)
 	return buf, nil
 }
+
+// GormDataType implements gorm.GormDataTypeInterface.
+func (mp *merkleProof) GormDataType() string {
+	return "bytes"
+}
+
+// Scan scans value into mp, implements sql.Scanner interface.
+func (mp *merkleProof) Scan(value interface{}) error {
+	bytes, ok := value.([]byte)
+	if !ok {
+		return errors.New(fmt.Sprint("failed to unmarshal merkleProof value:", value))
+	} else if len(bytes) == 0 || len(bytes)%proofHashSize != 0 {
+		return fmt.Errorf("failed to unmarshal merkleProof value due to invalid number of bytes %v", len(bytes))
+	}
+
+	n := len(bytes) / proofHashSize
+	mp.proof = make([]types.Hash256, n)
+	for i := 0; i < n; i++ {
+		copy(mp.proof[i][:], bytes[:proofHashSize])
+		bytes = bytes[proofHashSize:]
+	}
+	return nil
+}
+
+// Value returns a merkle proof value, implements driver.Valuer interface.
+func (mp merkleProof) Value() (driver.Value, error) {
+	var i int
+	out := make([]byte, len(mp.proof)*proofHashSize)
+	for _, ph := range mp.proof {
+		i += copy(out[i:], ph[:])
+	}
+	return out, nil
+}
diff --git a/stores/types_test.go b/stores/types_test.go
new file mode 100644
index 000000000..a4c8628a9
--- /dev/null
+++ b/stores/types_test.go
@@ -0,0 +1,154 @@
+package stores
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"testing"
+
+	"go.sia.tech/core/types"
+)
+
+func TestTypeCurrency(t *testing.T) {
+	ss := newTestSQLStore(t, defaultTestSQLStoreConfig)
+	defer ss.Close()
+
+	// prepare the table
+	if isSQLite(ss.db) {
+		if err := ss.db.Exec("CREATE TABLE currencies (id INTEGER PRIMARY KEY AUTOINCREMENT,c BLOB);").Error; err != nil {
+			t.Fatal(err)
+		}
+	} else {
+		if err := ss.db.Exec("CREATE TABLE currencies (id INT AUTO_INCREMENT PRIMARY KEY, c BLOB);").Error; err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	// insert currencies in random order
+	if err := ss.db.Exec("INSERT INTO currencies (c) VALUES (?),(?),(?);", bCurrency(types.MaxCurrency), bCurrency(types.NewCurrency64(1)), bCurrency(types.ZeroCurrency)).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	// fetch currencies and assert they're sorted
+	var currencies []bCurrency
+	if err := ss.db.Raw(`SELECT c FROM currencies ORDER BY c ASC`).Scan(&currencies).Error; err != nil {
+		t.Fatal(err)
+	} else if !sort.SliceIsSorted(currencies, func(i, j int) bool {
+		return types.Currency(currencies[i]).Cmp(types.Currency(currencies[j])) < 0
+	}) {
+		t.Fatal("currencies not sorted", currencies)
+	}
+
+	// convenience variables
+	c0 := currencies[0]
+	c1 := currencies[1]
+	cM := currencies[2]
+
+	tests := []struct {
+		a   bCurrency
+		b   bCurrency
+		cmp string
+	}{
+		{
+			a:   c0,
+			b:   c1,
+			cmp: "<",
+		},
+		{
+			a:   c1,
+			b:   c0,
+			cmp: ">",
+		},
+		{
+			a:   c0,
+			b:   c1,
+			cmp: "!=",
+		},
+		{
+			a:   c1,
+			b:   c1,
+			cmp: "=",
+		},
+		{
+			a:   c0,
+			b:   cM,
+			cmp: "<",
+		},
+		{
+			a:   cM,
+			b:   c0,
+			cmp: ">",
+		},
+		{
+			a:   cM,
+			b:   cM,
+			cmp: "=",
+		},
+	}
+	for i, test := range tests {
+		var result bool
+		query := fmt.Sprintf("SELECT ? %s ?", test.cmp)
+		if !isSQLite(ss.db) {
+			query = strings.Replace(query, "?", "HEX(?)", -1)
+		}
+		if err := ss.db.Raw(query, test.a, test.b).Scan(&result).Error; err != nil {
+			t.Fatal(err)
+		} else if !result {
+			t.Errorf("unexpected result in case %d/%d: expected %v %s %v to be true", i+1, len(tests), types.Currency(test.a).String(), test.cmp, types.Currency(test.b).String())
+		} else if test.cmp == "<" && types.Currency(test.a).Cmp(types.Currency(test.b)) >= 0 {
+			t.Fatal("invalid result")
+		} else if test.cmp == ">" && types.Currency(test.a).Cmp(types.Currency(test.b)) <= 0 {
+			t.Fatal("invalid result")
+		} else if test.cmp == "=" && types.Currency(test.a).Cmp(types.Currency(test.b)) != 0 {
+			t.Fatal("invalid result")
+		}
+	}
+}
+
+func TestTypeMerkleProof(t *testing.T) {
+	ss := newTestSQLStore(t, defaultTestSQLStoreConfig)
+	defer ss.Close()
+
+	// prepare the table
+	if isSQLite(ss.db) {
+		if err := ss.db.Exec("CREATE TABLE merkle_proofs (id INTEGER PRIMARY KEY AUTOINCREMENT,merkle_proof BLOB);").Error; err != nil {
+			t.Fatal(err)
+		}
+	} else {
+		ss.db.Exec("DROP TABLE IF EXISTS merkle_proofs;")
+		if err := ss.db.Exec("CREATE TABLE merkle_proofs (id INT AUTO_INCREMENT PRIMARY KEY, merkle_proof BLOB);").Error; err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	// insert merkle proof
+	mp1 := merkleProof{proof: []types.Hash256{{3}, {1}, {2}}}
+	mp2 := merkleProof{proof: []types.Hash256{{4}}}
+	if err := ss.db.Exec("INSERT INTO merkle_proofs (merkle_proof) VALUES (?), (?);", mp1, mp2).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	// fetch first proof
+	var first merkleProof
+	if err := ss.db.
+		Raw(`SELECT merkle_proof FROM merkle_proofs`).
+		Take(&first).
+		Error; err != nil {
+		t.Fatal(err)
+	} else if first.proof[0] != (types.Hash256{3}) || first.proof[1] != (types.Hash256{1}) || first.proof[2] != (types.Hash256{2}) {
+		t.Fatalf("unexpected proof %+v", first)
+	}
+
+	// fetch both proofs
+	var both []merkleProof
+	if err := ss.db.
+		Raw(`SELECT merkle_proof FROM merkle_proofs`).
+		Scan(&both).
+		Error; err != nil {
+		t.Fatal(err)
+	} else if len(both) != 2 {
+		t.Fatalf("unexpected number of proofs: %d", len(both))
+	} else if both[1].proof[0] != (types.Hash256{4}) {
+		t.Fatalf("unexpected proof %+v", both)
+	}
+}