diff --git a/api/docgen/docgen.go b/api/docgen/docgen.go
index bacb751e2..221e8e17a 100644
--- a/api/docgen/docgen.go
+++ b/api/docgen/docgen.go
@@ -378,8 +378,11 @@ func init() {
 	ethFeeHistoryReward := [][]api.EthBigInt{}
 	addExample(&ethFeeHistoryReward)
 
-	addExample(api.EthFilterID("c5564560217c43e4bc0484df655e9019"))
-	addExample(api.EthSubscriptionID("b62df77831484129adf6682332ad0725"))
+	filterid, _ := api.EthHashFromHex("0x5CbEeC012345673f25E309Cc264f240bb0664031")
+	addExample(api.EthFilterID(filterid))
+
+	subid, _ := api.EthHashFromHex("0x5CbEeCF99d3fDB301234567c264f240bb0664031")
+	addExample(api.EthSubscriptionID(subid))
 
 	pstring := func(s string) *string { return &s }
 	addExample(&api.EthFilterSpec{
diff --git a/api/eth_types.go b/api/eth_types.go
index 57937ad8c..4708239ca 100644
--- a/api/eth_types.go
+++ b/api/eth_types.go
@@ -418,10 +418,10 @@ type EthFeeHistory struct {
 }
 
 // An opaque identifier generated by the Lotus node to refer to an installed filter.
-type EthFilterID string
+type EthFilterID EthHash
 
 // An opaque identifier generated by the Lotus node to refer to an active subscription.
-type EthSubscriptionID string
+type EthSubscriptionID EthHash
 
 type EthFilterSpec struct {
 	// Interpreted as an epoch or one of "latest" for last mined block, "earliest" for first,
diff --git a/api/eth_types_test.go b/api/eth_types_test.go
index 1036a6f79..d65a32625 100644
--- a/api/eth_types_test.go
+++ b/api/eth_types_test.go
@@ -176,7 +176,7 @@ func TestEthFilterResultMarshalJSON(t *testing.T) {
 		BlockHash:        hash2,
 		BlockNumber:      53,
 		Topics:           []EthBytes{hash1[:]},
-		Data:             hash1[:],
+		Data:             []EthBytes{hash1[:]},
 		Address:          addr,
 	}
 	logjson, err := json.Marshal(log)
diff --git a/chain/events/filter/event.go b/chain/events/filter/event.go
index f5f2123ad..2f4d3206f 100644
--- a/chain/events/filter/event.go
+++ b/chain/events/filter/event.go
@@ -7,7 +7,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	"golang.org/x/xerrors"
@@ -24,7 +23,7 @@ import (
 const indexed uint8 = 0x01
 
 type EventFilter struct {
-	id         string
+	id         FilterID
 	minHeight  abi.ChainEpoch // minimum epoch to apply filter or -1 if no minimum
 	maxHeight  abi.ChainEpoch // maximum epoch to apply filter or -1 if no maximum
 	tipsetCid  cid.Cid
@@ -51,7 +50,7 @@ type CollectedEvent struct {
 	MsgCid      cid.Cid         // cid of message that produced event
 }
 
-func (f *EventFilter) ID() string {
+func (f *EventFilter) ID() FilterID {
 	return f.id
 }
 
@@ -290,7 +289,7 @@ type EventFilterManager struct {
 	EventIndex       *EventIndex
 
 	mu            sync.Mutex // guards mutations to filters
-	filters       map[string]*EventFilter
+	filters       map[FilterID]*EventFilter
 	currentHeight abi.ChainEpoch
 }
 
@@ -365,13 +364,13 @@ func (m *EventFilterManager) Install(ctx context.Context, minHeight, maxHeight a
 		return nil, xerrors.Errorf("historic event index disabled")
 	}
 
-	id, err := uuid.NewRandom()
+	id, err := newFilterID()
 	if err != nil {
-		return nil, xerrors.Errorf("new uuid: %w", err)
+		return nil, xerrors.Errorf("new filter id: %w", err)
 	}
 
 	f := &EventFilter{
-		id:         id.String(),
+		id:         id,
 		minHeight:  minHeight,
 		maxHeight:  maxHeight,
 		tipsetCid:  tipsetCid,
@@ -389,15 +388,15 @@ func (m *EventFilterManager) Install(ctx context.Context, minHeight, maxHeight a
 
 	m.mu.Lock()
 	if m.filters == nil {
-		m.filters = make(map[string]*EventFilter)
+		m.filters = make(map[FilterID]*EventFilter)
 	}
-	m.filters[id.String()] = f
+	m.filters[id] = f
 	m.mu.Unlock()
 
 	return f, nil
 }
 
-func (m *EventFilterManager) Remove(ctx context.Context, id string) error {
+func (m *EventFilterManager) Remove(ctx context.Context, id FilterID) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	if _, found := m.filters[id]; !found {
diff --git a/chain/events/filter/mempool.go b/chain/events/filter/mempool.go
index 5be350644..addae7bf1 100644
--- a/chain/events/filter/mempool.go
+++ b/chain/events/filter/mempool.go
@@ -5,7 +5,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"
 
@@ -14,7 +13,7 @@ import (
 )
 
 type MemPoolFilter struct {
-	id         string
+	id         FilterID
 	maxResults int // maximum number of results to collect, 0 is unlimited
 	ch         chan<- interface{}
 
@@ -25,7 +24,7 @@ type MemPoolFilter struct {
 
 var _ Filter = (*MemPoolFilter)(nil)
 
-func (f *MemPoolFilter) ID() string {
+func (f *MemPoolFilter) ID() FilterID {
 	return f.id
 }
 
@@ -79,7 +78,7 @@ type MemPoolFilterManager struct {
 	MaxFilterResults int
 
 	mu      sync.Mutex // guards mutations to filters
-	filters map[string]*MemPoolFilter
+	filters map[FilterID]*MemPoolFilter
 }
 
 func (m *MemPoolFilterManager) WaitForMpoolUpdates(ctx context.Context, ch <-chan api.MpoolUpdate) {
@@ -113,27 +112,27 @@ func (m *MemPoolFilterManager) processUpdate(ctx context.Context, u api.MpoolUpd
 }
 
 func (m *MemPoolFilterManager) Install(ctx context.Context) (*MemPoolFilter, error) {
-	id, err := uuid.NewRandom()
+	id, err := newFilterID()
 	if err != nil {
-		return nil, xerrors.Errorf("new uuid: %w", err)
+		return nil, xerrors.Errorf("new filter id: %w", err)
 	}
 
 	f := &MemPoolFilter{
-		id:         id.String(),
+		id:         id,
 		maxResults: m.MaxFilterResults,
 	}
 
 	m.mu.Lock()
 	if m.filters == nil {
-		m.filters = make(map[string]*MemPoolFilter)
+		m.filters = make(map[FilterID]*MemPoolFilter)
 	}
-	m.filters[id.String()] = f
+	m.filters[id] = f
 	m.mu.Unlock()
 
 	return f, nil
 }
 
-func (m *MemPoolFilterManager) Remove(ctx context.Context, id string) error {
+func (m *MemPoolFilterManager) Remove(ctx context.Context, id FilterID) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	if _, found := m.filters[id]; !found {
diff --git a/chain/events/filter/store.go b/chain/events/filter/store.go
index 2f8a09875..9f201fc38 100644
--- a/chain/events/filter/store.go
+++ b/chain/events/filter/store.go
@@ -5,10 +5,13 @@ import (
 	"errors"
 	"sync"
 	"time"
+
+	"github.com/google/uuid"
+	"golang.org/x/xerrors"
 )
 
 type Filter interface {
-	ID() string
+	ID() FilterID
 	LastTaken() time.Time
 	SetSubChannel(chan<- interface{})
 	ClearSubChannel()
@@ -16,8 +19,8 @@ type Filter interface {
 
 type FilterStore interface {
 	Add(context.Context, Filter) error
-	Get(context.Context, string) (Filter, error)
-	Remove(context.Context, string) error
+	Get(context.Context, FilterID) (Filter, error)
+	Remove(context.Context, FilterID) error
 	NotTakenSince(when time.Time) []Filter // returns a list of filters that have not had their collected results taken
 }
 
@@ -27,10 +30,22 @@ var (
 	ErrMaximumNumberOfFilters  = errors.New("maximum number of filters registered")
 )
 
+type FilterID [32]byte // compatible with EthHash
+
+func newFilterID() (FilterID, error) {
+	rawid, err := uuid.NewRandom()
+	if err != nil {
+		return FilterID{}, xerrors.Errorf("new uuid: %w", err)
+	}
+	id := FilterID{}
+	copy(id[:], rawid[:]) // uuid is 16 bytes
+	return id, nil
+}
+
 type memFilterStore struct {
 	max     int
 	mu      sync.Mutex
-	filters map[string]Filter
+	filters map[FilterID]Filter
 }
 
 var _ FilterStore = (*memFilterStore)(nil)
@@ -38,7 +53,7 @@ var _ FilterStore = (*memFilterStore)(nil)
 func NewMemFilterStore(maxFilters int) FilterStore {
 	return &memFilterStore{
 		max:     maxFilters,
-		filters: make(map[string]Filter),
+		filters: make(map[FilterID]Filter),
 	}
 }
 
@@ -57,7 +72,7 @@ func (m *memFilterStore) Add(_ context.Context, f Filter) error {
 	return nil
 }
 
-func (m *memFilterStore) Get(_ context.Context, id string) (Filter, error) {
+func (m *memFilterStore) Get(_ context.Context, id FilterID) (Filter, error) {
 	m.mu.Lock()
 	f, found := m.filters[id]
 	m.mu.Unlock()
@@ -67,7 +82,7 @@ func (m *memFilterStore) Get(_ context.Context, id string) (Filter, error) {
 	return f, nil
 }
 
-func (m *memFilterStore) Remove(_ context.Context, id string) error {
+func (m *memFilterStore) Remove(_ context.Context, id FilterID) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
diff --git a/chain/events/filter/tipset.go b/chain/events/filter/tipset.go
index 0e43c96ef..d3ad8b67b 100644
--- a/chain/events/filter/tipset.go
+++ b/chain/events/filter/tipset.go
@@ -5,14 +5,13 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/chain/types"
 )
 
 type TipSetFilter struct {
-	id         string
+	id         FilterID
 	maxResults int // maximum number of results to collect, 0 is unlimited
 	ch         chan<- interface{}
 
@@ -23,7 +22,7 @@ type TipSetFilter struct {
 
 var _ Filter = (*TipSetFilter)(nil)
 
-func (f *TipSetFilter) ID() string {
+func (f *TipSetFilter) ID() FilterID {
 	return f.id
 }
 
@@ -77,7 +76,7 @@ type TipSetFilterManager struct {
 	MaxFilterResults int
 
 	mu      sync.Mutex // guards mutations to filters
-	filters map[string]*TipSetFilter
+	filters map[FilterID]*TipSetFilter
 }
 
 func (m *TipSetFilterManager) Apply(ctx context.Context, from, to *types.TipSet) error {
@@ -100,27 +99,27 @@ func (m *TipSetFilterManager) Revert(ctx context.Context, from, to *types.TipSet
 }
 
 func (m *TipSetFilterManager) Install(ctx context.Context) (*TipSetFilter, error) {
-	id, err := uuid.NewRandom()
+	id, err := newFilterID()
 	if err != nil {
-		return nil, xerrors.Errorf("new uuid: %w", err)
+		return nil, xerrors.Errorf("new filter id: %w", err)
 	}
 
 	f := &TipSetFilter{
-		id:         id.String(),
+		id:         id,
 		maxResults: m.MaxFilterResults,
 	}
 
 	m.mu.Lock()
 	if m.filters == nil {
-		m.filters = make(map[string]*TipSetFilter)
+		m.filters = make(map[FilterID]*TipSetFilter)
 	}
-	m.filters[id.String()] = f
+	m.filters[id] = f
 	m.mu.Unlock()
 
 	return f, nil
 }
 
-func (m *TipSetFilterManager) Remove(ctx context.Context, id string) error {
+func (m *TipSetFilterManager) Remove(ctx context.Context, id FilterID) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	if _, found := m.filters[id]; !found {
diff --git a/itests/eth_filter_test.go b/itests/eth_filter_test.go
index 45c70b289..8c900bbf1 100644
--- a/itests/eth_filter_test.go
+++ b/itests/eth_filter_test.go
@@ -294,11 +294,11 @@ func TestEthNewFilterCatchAll(t *testing.T) {
 	// expect to have seen iteration number of events
 	require.Equal(iterations, len(res.Results))
 
-	topic1Hash := api.EthHashData([]byte{0x42, 0x11, 0x11})
-	topic2Hash := api.EthHashData([]byte{0x42, 0x22, 0x22})
-	topic3Hash := api.EthHashData([]byte{0x42, 0x33, 0x33})
-	topic4Hash := api.EthHashData([]byte{0x42, 0x44, 0x44})
-	data1Hash := api.EthHashData([]byte{0x48, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88})
+	topic1 := api.EthBytes(leftpad32([]byte{0x11, 0x11}))
+	topic2 := api.EthBytes(leftpad32([]byte{0x22, 0x22}))
+	topic3 := api.EthBytes(leftpad32([]byte{0x33, 0x33}))
+	topic4 := api.EthBytes(leftpad32([]byte{0x44, 0x44}))
+	data1 := api.EthBytes(leftpad32([]byte{0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88}))
 
 	for _, r := range res.Results {
 		// since response is a union and Go doesn't support them well, go-jsonrpc won't give us typed results
@@ -323,13 +323,12 @@ func TestEthNewFilterCatchAll(t *testing.T) {
 		require.Equal(tsCidHash, elog.BlockHash, "block hash")
 
 		require.Equal(4, len(elog.Topics), "number of topics")
-		require.Equal(topic1Hash, elog.Topics[0], "topic1")
-		require.Equal(topic2Hash, elog.Topics[1], "topic2")
-		require.Equal(topic3Hash, elog.Topics[2], "topic3")
-		require.Equal(topic4Hash, elog.Topics[3], "topic4")
+		require.Equal(topic1, elog.Topics[0], "topic1")
+		require.Equal(topic2, elog.Topics[1], "topic2")
+		require.Equal(topic3, elog.Topics[2], "topic3")
+		require.Equal(topic4, elog.Topics[3], "topic4")
 
-		require.Equal(1, len(elog.Data), "number of data")
-		require.Equal(data1Hash, elog.Data[0], "data1")
+		require.Equal(data1, elog.Data, "data1")
 
 	}
 }
@@ -368,67 +367,76 @@ func ParseEthLog(in map[string]interface{}) (*api.EthLog, error) {
 			}
 			s, ok := v.(string)
 			if !ok {
-				return nil, xerrors.Errorf(k + " not a string")
+				return nil, xerrors.Errorf(k + ": not a string")
 			}
 			el.Removed, err = strconv.ParseBool(s)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "address":
 			s, ok := v.(string)
 			if !ok {
-				return nil, xerrors.Errorf(k + " not a string")
+				return nil, xerrors.Errorf(k + ": not a string")
 			}
 			el.Address, err = api.EthAddressFromHex(s)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "logIndex":
 			el.LogIndex, err = ethUint64(k, v)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "transactionIndex":
 			el.TransactionIndex, err = ethUint64(k, v)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "blockNumber":
 			el.BlockNumber, err = ethUint64(k, v)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "transactionHash":
 			el.TransactionHash, err = ethHash(k, v)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "blockHash":
 			el.BlockHash, err = ethHash(k, v)
 			if err != nil {
-				return nil, err
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
 		case "data":
-			sl, ok := v.([]interface{})
+			s, ok := v.(string)
 			if !ok {
-				return nil, xerrors.Errorf(k + " not a slice")
+				return nil, xerrors.Errorf(k + ": not a string")
 			}
-			for _, s := range sl {
-				data, err := hex.DecodeString(s.(string))
-				if err != nil {
-					return nil, err
-				}
-				el.Data = data
+			data, err := hex.DecodeString(s[2:])
+			if err != nil {
+				return nil, xerrors.Errorf("%s: %w", k, err)
 			}
+			el.Data = data
+
 		case "topics":
+			s, ok := v.(string)
+			if ok {
+				topic, err := hex.DecodeString(s[2:])
+				if err != nil {
+					return nil, xerrors.Errorf("%s: %w", k, err)
+				}
+				el.Topics = append(el.Topics, topic)
+				continue
+			}
+
 			sl, ok := v.([]interface{})
 			if !ok {
-				return nil, xerrors.Errorf(k + " not a slice")
+				return nil, xerrors.Errorf(k + ": not a slice")
 			}
 			for _, s := range sl {
-				topic, err := hex.DecodeString(s.(string))
+				topic, err := hex.DecodeString(s.(string)[2:])
 				if err != nil {
-					return nil, err
+					return nil, xerrors.Errorf("%s: %w", k, err)
 				}
 				el.Topics = append(el.Topics, topic)
 			}
@@ -542,11 +550,11 @@ func TestEthGetLogsAll(t *testing.T) {
 	ethContractAddr, err := api.EthAddressFromFilecoinAddress(*actor.Address)
 	require.NoError(err)
 
-	topic1Hash := api.EthHashData([]byte{0x42, 0x11, 0x11})
-	topic2Hash := api.EthHashData([]byte{0x42, 0x22, 0x22})
-	topic3Hash := api.EthHashData([]byte{0x42, 0x33, 0x33})
-	topic4Hash := api.EthHashData([]byte{0x42, 0x44, 0x44})
-	data1Hash := api.EthHashData([]byte{0x48, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88})
+	topic1 := api.EthBytes(leftpad32([]byte{0x11, 0x11}))
+	topic2 := api.EthBytes(leftpad32([]byte{0x22, 0x22}))
+	topic3 := api.EthBytes(leftpad32([]byte{0x33, 0x33}))
+	topic4 := api.EthBytes(leftpad32([]byte{0x44, 0x44}))
+	data1 := api.EthBytes(leftpad32([]byte{0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88}))
 
 	pstring := func(s string) *string { return &s }
 
@@ -582,13 +590,12 @@ func TestEthGetLogsAll(t *testing.T) {
 		require.Equal(tsCidHash, elog.BlockHash, "block hash")
 
 		require.Equal(4, len(elog.Topics), "number of topics")
-		require.Equal(topic1Hash, elog.Topics[0], "topic1")
-		require.Equal(topic2Hash, elog.Topics[1], "topic2")
-		require.Equal(topic3Hash, elog.Topics[2], "topic3")
-		require.Equal(topic4Hash, elog.Topics[3], "topic4")
+		require.Equal(topic1, elog.Topics[0], "topic1")
+		require.Equal(topic2, elog.Topics[1], "topic2")
+		require.Equal(topic3, elog.Topics[2], "topic3")
+		require.Equal(topic4, elog.Topics[3], "topic4")
 
-		require.Equal(1, len(elog.Data), "number of data")
-		require.Equal(data1Hash, elog.Data[0], "data1")
+		require.Equal(data1, elog.Data, "data1")
 
 	}
 }
@@ -706,3 +713,13 @@ func TestEthSubscribeLogs(t *testing.T) {
 	// expect to have seen all logs
 	require.Equal(len(received), len(subResponses))
 }
+
+func leftpad32(orig []byte) []byte {
+	needed := 32 - len(orig)
+	if needed <= 0 {
+		return orig
+	}
+	ret := make([]byte, 32)
+	copy(ret[needed:], orig)
+	return ret
+}
diff --git a/node/impl/full/eth.go b/node/impl/full/eth.go
index feb7e0bb5..3f5e69110 100644
--- a/node/impl/full/eth.go
+++ b/node/impl/full/eth.go
@@ -696,7 +696,7 @@ func (e *EthEvent) EthGetFilterChanges(ctx context.Context, id api.EthFilterID)
 		return nil, api.ErrNotSupported
 	}
 
-	f, err := e.FilterStore.Get(ctx, string(id))
+	f, err := e.FilterStore.Get(ctx, filter.FilterID(id))
 	if err != nil {
 		return nil, err
 	}
@@ -718,7 +718,7 @@ func (e *EthEvent) EthGetFilterLogs(ctx context.Context, id api.EthFilterID) (*a
 		return nil, api.ErrNotSupported
 	}
 
-	f, err := e.FilterStore.Get(ctx, string(id))
+	f, err := e.FilterStore.Get(ctx, filter.FilterID(id))
 	if err != nil {
 		return nil, err
 	}
@@ -823,22 +823,22 @@ func (e *EthEvent) installEthFilterSpec(ctx context.Context, filterSpec *api.Eth
 
 func (e *EthEvent) EthNewFilter(ctx context.Context, filterSpec *api.EthFilterSpec) (api.EthFilterID, error) {
 	if e.FilterStore == nil || e.EventFilterManager == nil {
-		return "", api.ErrNotSupported
+		return api.EthFilterID{}, api.ErrNotSupported
 	}
 
 	f, err := e.installEthFilterSpec(ctx, filterSpec)
 	if err != nil {
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	if err := e.FilterStore.Add(ctx, f); err != nil {
 		// Could not record in store, attempt to delete filter to clean up
 		err2 := e.TipSetFilterManager.Remove(ctx, f.ID())
 		if err2 != nil {
-			return "", xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
+			return api.EthFilterID{}, xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
 		}
 
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	return api.EthFilterID(f.ID()), nil
@@ -846,22 +846,22 @@ func (e *EthEvent) EthNewFilter(ctx context.Context, filterSpec *api.EthFilterSp
 
 func (e *EthEvent) EthNewBlockFilter(ctx context.Context) (api.EthFilterID, error) {
 	if e.FilterStore == nil || e.TipSetFilterManager == nil {
-		return "", api.ErrNotSupported
+		return api.EthFilterID{}, api.ErrNotSupported
 	}
 
 	f, err := e.TipSetFilterManager.Install(ctx)
 	if err != nil {
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	if err := e.FilterStore.Add(ctx, f); err != nil {
 		// Could not record in store, attempt to delete filter to clean up
 		err2 := e.TipSetFilterManager.Remove(ctx, f.ID())
 		if err2 != nil {
-			return "", xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
+			return api.EthFilterID{}, xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
 		}
 
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	return api.EthFilterID(f.ID()), nil
@@ -869,22 +869,22 @@ func (e *EthEvent) EthNewBlockFilter(ctx context.Context) (api.EthFilterID, erro
 
 func (e *EthEvent) EthNewPendingTransactionFilter(ctx context.Context) (api.EthFilterID, error) {
 	if e.FilterStore == nil || e.MemPoolFilterManager == nil {
-		return "", api.ErrNotSupported
+		return api.EthFilterID{}, api.ErrNotSupported
 	}
 
 	f, err := e.MemPoolFilterManager.Install(ctx)
 	if err != nil {
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	if err := e.FilterStore.Add(ctx, f); err != nil {
 		// Could not record in store, attempt to delete filter to clean up
 		err2 := e.MemPoolFilterManager.Remove(ctx, f.ID())
 		if err2 != nil {
-			return "", xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
+			return api.EthFilterID{}, xerrors.Errorf("encountered error %v while removing new filter due to %v", err2, err)
 		}
 
-		return "", err
+		return api.EthFilterID{}, err
 	}
 
 	return api.EthFilterID(f.ID()), nil
@@ -895,7 +895,7 @@ func (e *EthEvent) EthUninstallFilter(ctx context.Context, id api.EthFilterID) (
 		return false, api.ErrNotSupported
 	}
 
-	f, err := e.FilterStore.Get(ctx, string(id))
+	f, err := e.FilterStore.Get(ctx, filter.FilterID(id))
 	if err != nil {
 		if errors.Is(err, filter.ErrFilterNotFound) {
 			return false, nil
@@ -956,7 +956,7 @@ func (e *EthEvent) EthSubscribe(ctx context.Context, eventType string, params *a
 		f, err := e.TipSetFilterManager.Install(ctx)
 		if err != nil {
 			// clean up any previous filters added and stop the sub
-			_, _ = e.EthUnsubscribe(ctx, api.EthSubscriptionID(sub.id))
+			_, _ = e.EthUnsubscribe(ctx, sub.id)
 			return nil, err
 		}
 		sub.addFilter(ctx, f)
@@ -978,7 +978,7 @@ func (e *EthEvent) EthSubscribe(ctx context.Context, eventType string, params *a
 		f, err := e.EventFilterManager.Install(ctx, -1, -1, cid.Undef, []address.Address{}, keys)
 		if err != nil {
 			// clean up any previous filters added and stop the sub
-			_, _ = e.EthUnsubscribe(ctx, api.EthSubscriptionID(sub.id))
+			_, _ = e.EthUnsubscribe(ctx, sub.id)
 			return nil, err
 		}
 		sub.addFilter(ctx, f)
@@ -994,7 +994,7 @@ func (e *EthEvent) EthUnsubscribe(ctx context.Context, id api.EthSubscriptionID)
 		return false, api.ErrNotSupported
 	}
 
-	filters, err := e.SubManager.StopSubscription(ctx, string(id))
+	filters, err := e.SubManager.StopSubscription(ctx, id)
 	if err != nil {
 		return false, nil
 	}
@@ -1130,14 +1130,16 @@ type EthSubscriptionManager struct {
 	StateAPI StateAPI
 	ChainAPI ChainAPI
 	mu       sync.Mutex
-	subs     map[string]*ethSubscription
+	subs     map[api.EthSubscriptionID]*ethSubscription
 }
 
 func (e *EthSubscriptionManager) StartSubscription(ctx context.Context) (*ethSubscription, error) { // nolint
-	id, err := uuid.NewRandom()
+	rawid, err := uuid.NewRandom()
 	if err != nil {
 		return nil, xerrors.Errorf("new uuid: %w", err)
 	}
+	id := api.EthSubscriptionID{}
+	copy(id[:], rawid[:]) // uuid is 16 bytes
 
 	ctx, quit := context.WithCancel(ctx)
 
@@ -1145,7 +1147,7 @@ func (e *EthSubscriptionManager) StartSubscription(ctx context.Context) (*ethSub
 		Chain:    e.Chain,
 		StateAPI: e.StateAPI,
 		ChainAPI: e.ChainAPI,
-		id:       id.String(),
+		id:       id,
 		in:       make(chan interface{}, 200),
 		out:      make(chan api.EthSubscriptionResponse, 20),
 		quit:     quit,
@@ -1153,7 +1155,7 @@ func (e *EthSubscriptionManager) StartSubscription(ctx context.Context) (*ethSub
 
 	e.mu.Lock()
 	if e.subs == nil {
-		e.subs = make(map[string]*ethSubscription)
+		e.subs = make(map[api.EthSubscriptionID]*ethSubscription)
 	}
 	e.subs[sub.id] = sub
 	e.mu.Unlock()
@@ -1163,7 +1165,7 @@ func (e *EthSubscriptionManager) StartSubscription(ctx context.Context) (*ethSub
 	return sub, nil
 }
 
-func (e *EthSubscriptionManager) StopSubscription(ctx context.Context, id string) ([]filter.Filter, error) {
+func (e *EthSubscriptionManager) StopSubscription(ctx context.Context, id api.EthSubscriptionID) ([]filter.Filter, error) {
 	e.mu.Lock()
 	defer e.mu.Unlock()
 
@@ -1181,7 +1183,7 @@ type ethSubscription struct {
 	Chain    *store.ChainStore
 	StateAPI StateAPI
 	ChainAPI ChainAPI
-	id       string
+	id       api.EthSubscriptionID
 	in       chan interface{}
 	out      chan api.EthSubscriptionResponse
 
@@ -1205,7 +1207,7 @@ func (e *ethSubscription) start(ctx context.Context) {
 			return
 		case v := <-e.in:
 			resp := api.EthSubscriptionResponse{
-				SubscriptionID: api.EthSubscriptionID(e.id),
+				SubscriptionID: e.id,
 			}
 
 			var err error