diff --git a/session/common.go b/session/common.go
index f75a3a9f..7e46491e 100644
--- a/session/common.go
+++ b/session/common.go
@@ -243,6 +243,11 @@ func (x *commonData) SetExp(exp uint64) {
 	x.exp = exp
 }
 
+// Exp returns "exp" (expiration time) claim.
+func (x commonData) Exp() uint64 {
+	return x.exp
+}
+
 // SetNbf sets "nbf" (not before) claim which identifies the time (in NeoFS
 // epochs) before which the session MUST NOT be accepted for processing.
 // The processing of the "nbf" claim requires that the current date/time MUST be
@@ -255,6 +260,11 @@ func (x *commonData) SetNbf(nbf uint64) {
 	x.nbf = nbf
 }
 
+// Nbf returns "nbf" (not before) claim.
+func (x commonData) Nbf() uint64 {
+	return x.nbf
+}
+
 // SetIat sets "iat" (issued at) claim which identifies the time (in NeoFS
 // epochs) at which the session was issued. This claim can be used to
 // determine the age of the session.
@@ -266,8 +276,13 @@ func (x *commonData) SetIat(iat uint64) {
 	x.iat = iat
 }
 
+// Iat returns "iat" (issued at) claim.
+func (x commonData) Iat() uint64 {
+	return x.iat
+}
+
 func (x commonData) expiredAt(epoch uint64) bool {
-	return x.exp < epoch
+	return x.Exp() < epoch
 }
 
 // InvalidAt asserts "exp", "nbf" and "iat" claims.
@@ -276,7 +291,7 @@ func (x commonData) expiredAt(epoch uint64) bool {
 //
 // See also SetExp, SetNbf, SetIat.
 func (x commonData) InvalidAt(epoch uint64) bool {
-	return x.expiredAt(epoch) || x.nbf > epoch || x.iat > epoch
+	return x.expiredAt(epoch) || x.Nbf() > epoch || x.Iat() > epoch
 }
 
 // SetID sets a unique identifier for the session. The identifier value MUST be
diff --git a/session/common_test.go b/session/common_test.go
new file mode 100644
index 00000000..22d64366
--- /dev/null
+++ b/session/common_test.go
@@ -0,0 +1,47 @@
+package session_test
+
+import (
+	"testing"
+
+	"github.com/nspcc-dev/neofs-sdk-go/session"
+	"github.com/stretchr/testify/require"
+)
+
+func testLifetimeClaim[T session.Container | session.Object](t testing.TB, get func(T) uint64, set func(*T, uint64)) {
+	var x T
+	require.Zero(t, get(x))
+	set(&x, 12094032)
+	require.EqualValues(t, 12094032, get(x))
+	set(&x, 5469830342)
+	require.EqualValues(t, 5469830342, get(x))
+}
+
+type lifetime interface {
+	SetExp(uint64)
+	SetIat(uint64)
+	SetNbf(uint64)
+	InvalidAt(uint64) bool
+}
+
+func testInvalidAt(t testing.TB, x lifetime) {
+	require.False(t, x.InvalidAt(0))
+
+	const iat = 13
+	const nbf = iat + 1
+	const exp = nbf + 1
+
+	x.SetIat(iat)
+	x.SetNbf(nbf)
+	x.SetExp(exp)
+
+	require.True(t, x.InvalidAt(iat-1))
+	require.True(t, x.InvalidAt(iat))
+	require.False(t, x.InvalidAt(nbf))
+	require.False(t, x.InvalidAt(exp))
+	require.True(t, x.InvalidAt(exp+1))
+}
+
+func TestInvalidAt(t *testing.T) {
+	testInvalidAt(t, new(session.Container))
+	testInvalidAt(t, new(session.Object))
+}
diff --git a/session/container_test.go b/session/container_test.go
index e322c843..caae3a49 100644
--- a/session/container_test.go
+++ b/session/container_test.go
@@ -152,10 +152,9 @@ func TestContainerProtocolV2(t *testing.T) {
 			},
 			restore: restoreLifetime,
 			assert: func(val session.Container) {
-				require.True(t, val.InvalidAt(1))
-				require.False(t, val.InvalidAt(2))
-				require.False(t, val.InvalidAt(3))
-				require.True(t, val.InvalidAt(4))
+				require.EqualValues(t, 1, val.Iat())
+				require.EqualValues(t, 2, val.Nbf())
+				require.EqualValues(t, 3, val.Exp())
 			},
 			breakSign: func(m *v2session.Token) {
 				lt := m.GetBody().GetLifetime()
@@ -624,3 +623,15 @@ func TestContainer_VerifyDataSignature(t *testing.T) {
 	require.False(t, tok.VerifySessionDataSignature(append(data, 1), sigV2.GetSign()))
 	require.False(t, tok.VerifySessionDataSignature(data, append(sigV2.GetSign(), 1)))
 }
+
+func TestContainer_SetExp(t *testing.T) {
+	testLifetimeClaim(t, session.Container.Exp, (*session.Container).SetExp)
+}
+
+func TestContainer_SetIat(t *testing.T) {
+	testLifetimeClaim(t, session.Container.Iat, (*session.Container).SetIat)
+}
+
+func TestContainer_SetNbf(t *testing.T) {
+	testLifetimeClaim(t, session.Container.Nbf, (*session.Container).SetNbf)
+}
diff --git a/session/object_test.go b/session/object_test.go
index 1449fdaa..d275cd35 100644
--- a/session/object_test.go
+++ b/session/object_test.go
@@ -157,10 +157,9 @@ func TestObjectProtocolV2(t *testing.T) {
 			},
 			restore: restoreLifetime,
 			assert: func(val session.Object) {
-				require.True(t, val.InvalidAt(1))
-				require.False(t, val.InvalidAt(2))
-				require.False(t, val.InvalidAt(3))
-				require.True(t, val.InvalidAt(4))
+				require.EqualValues(t, 1, val.Iat())
+				require.EqualValues(t, 2, val.Nbf())
+				require.EqualValues(t, 3, val.Exp())
 			},
 			breakSign: func(m *v2session.Token) {
 				lt := m.GetBody().GetLifetime()
@@ -681,3 +680,15 @@ func TestObject_SignedData(t *testing.T) {
 
 	usertest.TestSignedData(t, issuer, &tokenSession)
 }
+
+func TestObject_SetExp(t *testing.T) {
+	testLifetimeClaim(t, session.Object.Exp, (*session.Object).SetExp)
+}
+
+func TestObject_SetIat(t *testing.T) {
+	testLifetimeClaim(t, session.Object.Iat, (*session.Object).SetIat)
+}
+
+func TestObject_SetNbf(t *testing.T) {
+	testLifetimeClaim(t, session.Object.Nbf, (*session.Object).SetNbf)
+}