diff --git a/tlsn/tlsn-core/src/substrings/proof.rs b/tlsn/tlsn-core/src/substrings/proof.rs
index ec3e051ff5..f726631c8c 100644
--- a/tlsn/tlsn-core/src/substrings/proof.rs
+++ b/tlsn/tlsn-core/src/substrings/proof.rs
@@ -68,14 +68,14 @@ impl SubstringsProof {
         for comm in self.inclusion_proof.commitments().iter() {
             if comm.direction() == &Direction::Sent {
                 for r in comm.ranges() {
-                    if r.end >= header.sent_len() {
+                    if r.end > header.sent_len() {
                         return Err(Error::ValidationError);
                     }
                 }
             } else {
                 // comm.direction() == &Direction::Received
                 for r in comm.ranges() {
-                    if r.end >= header.recv_len() {
+                    if r.end > header.recv_len() {
                         return Err(Error::ValidationError);
                     }
                 }
diff --git a/tlsn/tlsn-core/src/transcript.rs b/tlsn/tlsn-core/src/transcript.rs
index 3e0a977d28..0162f2940e 100644
--- a/tlsn/tlsn-core/src/transcript.rs
+++ b/tlsn/tlsn-core/src/transcript.rs
@@ -44,7 +44,7 @@ impl Transcript {
 
         let mut dst: Vec<u8> = Vec::new();
         for r in ranges {
-            if r.end as usize >= self.data.len() {
+            if r.end as usize > self.data.len() {
                 // range bounds must be within `src` length
                 return Err(Error::InternalError);
             } else {