diff --git a/.github/workflows/tests_scripts.yml b/.github/workflows/tests_scripts.yml
index 1f8d012b..88a473b6 100644
--- a/.github/workflows/tests_scripts.yml
+++ b/.github/workflows/tests_scripts.yml
@@ -4,36 +4,71 @@ on:
   push:
     paths:
       - scripts/sign_verify_file_ssh.sh
+      - .github/workflows/tests_scripts.yml
   pull_request:
     paths:
       - scripts/sign_verify_file_ssh.sh
+      - .github/workflows/tests_scripts.yml
 permissions:
   contents: read # to fetch code (actions/checkout)
 jobs:
   build:
     runs-on: ubuntu-24.04
     steps:
-    - name: checkout
-      uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
 
-    - name: test sign_verify_file_ssh.sh script
-      run: |
-          # Create a PEM format ssh identity
+      - name: Prepare SSH key pair, file and signature
+        run: |
           ssh-keygen -t rsa -b 4096 -m PEM -f id_rsa.pem -N ""
-          # Create a file to sign
           echo "Very important stuff" > out.txt
           export FILE_TO_SIGN="out.txt"
-          # Sign the file
-          ./scripts/sign_verify_file_ssh.sh sign id_rsa.pem "$FILE_TO_SIGN"
-          # Create an allowed_signers file based on the public key
-          echo -n "allowed_identity " > allowed_signers
+          ./scripts/sign_verify_file_ssh.sh --sign --private-key id_rsa.pem --file "$FILE_TO_SIGN" --namespace ci
+
+      - name: Create allowed signers file and verify
+        run: |
+          valid_before=$(date --date='today+3days' +%Y%m%d)
+          echo -n 'allowed_identity namespaces="ci",valid-before="'$valid_before'" ' > allowed_signers
           cat id_rsa.pem.pub >> allowed_signers
-          # Verify the signature
-          ./scripts/sign_verify_file_ssh.sh verify allowed_signers "$FILE_TO_SIGN"
-          # Make a new signature that does not appear in the allowed signers file
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt
+
+      - name: Replace allowed signers with disallowed identity
+        run: |
+          valid_before=$(date --date='today+3days' +%Y%m%d)
           ssh-keygen -t rsa -b 4096 -m PEM -f id_rsa.alt.pem -N ""
-          # Replace the allowed signers file
-          echo -n "disallowed_identity " > allowed_signers
+          echo -n 'disallowed_identity namespaces="ci",valid-before="'$valid_before'" ' > allowed_signers
           cat id_rsa.alt.pem.pub >> allowed_signers
-          # Make sure signature checking fails in this case
-          ./scripts/sign_verify_file_ssh.sh verify allowed_signers "$FILE_TO_SIGN" && exit 1 || echo "Expected failure for unknown identity"
+
+      - name: Ensure verification fails for unknown identity
+        run: |
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt && exit 1 || echo "Expected failure for unknown identity"
+
+      - name: Replace allowed signers with wrong namespace
+        run: |
+          valid_before=$(date --date='today+3days' +%Y%m%d)
+          echo -n 'wrong_namespace_identity namespaces="CI",valid-before="'$valid_before'" ' > allowed_signers
+          cat id_rsa.pem.pub >> allowed_signers
+
+      - name: Ensure verification fails for wrong namespace
+        run: |
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt && exit 2 || echo "Expected failure for wrong namespace"
+
+      - name: Replace allowed signers with expired key
+        run: |
+          valid_expired=$(date --date='today-3days' +%Y%m%d)
+          echo -n 'expired_key_identity namespaces="ci",valid-before="'$valid_expired'" ' > allowed_signers
+          cat id_rsa.pem.pub >> allowed_signers
+
+      - name: Ensure verification fails for expired key
+        run: |
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt && exit 3 || echo "Expected failure for expired key"
+
+      - name: Ensure verification when looping through allowed signers file
+        run: |
+          # Add the approved identity to the end
+          valid_before=$(date --date='today+3days' +%Y%m%d)
+          echo -n 'listed_identity namespaces="ci",valid-before="'$valid_before'" ' >> allowed_signers
+          cat id_rsa.pem.pub >> allowed_signers
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt
+          # Make sure we get exactly what we want in terse mode
+          ./scripts/sign_verify_file_ssh.sh --verify --allowed-signers-file allowed_signers --file out.txt --terse | grep -q '{\"identity\": \"listed_identity\", \"namespace\": \"ci\"}'
diff --git a/scripts/eessi-upload-to-staging b/scripts/eessi-upload-to-staging
index 25fd9675..fa3d7f57 100755
--- a/scripts/eessi-upload-to-staging
+++ b/scripts/eessi-upload-to-staging
@@ -75,6 +75,8 @@ function display_help
   echo "                                    expansion will be applied; arg '-l'"   >&2
   echo "                                    lists variables that are defined at"   >&2
   echo "                                    the time of expansion"                 >&2
+  echo "  -b | --bot-instance NAME       -  name of the bot instance that uploads" >&2
+  echo "                                    files to S3"                           >&2
   echo "  -e | --endpoint-url URL        -  endpoint url (needed for non AWS S3)"  >&2
   echo "  -h | --help                    -  display this usage information"        >&2
   echo "  -i | --pr-comment-id           -  identifier of a PR comment; may be"    >&2
@@ -134,6 +136,7 @@ sign_key=
 sign_script=
 
 # provided via options in the bot's config file app.cfg and/or command line argument
+bot_instance=
 metadata_prefix=
 artefact_prefix=
 
@@ -147,6 +150,10 @@ while [[ $# -gt 0 ]]; do
       artefact_prefix="$2"
       shift 2
       ;;
+    -b|--bot-instance)
+      bot_instance="$2"
+      shift 2
+      ;;
     -e|--endpoint-url)
       endpoint_url="$2"
       shift 2
@@ -263,7 +270,7 @@ for file in "$*"; do
         # 1st sign artefact, and upload signature
         if [[ "${sign}" = "1" ]]; then
           # sign artefact
-          ${sign_script} sign ${sign_key} ${file}
+          ${sign_script} --sign --private-key ${sign_key} --file ${file} --namespace ${bot_instance}
           # TODO check if signing worked (just check exit code == 0)
           sig_file=${file}.sig
           aws_sig_file=${aws_file}.sig
@@ -314,7 +321,7 @@ for file in "$*"; do
         # 2nd sign metadata file, and upload signature
         if [[ "${sign}" = "1" ]]; then
           # sign metadata file
-          ${sign_script} sign ${sign_key} ${metadata_file}
+          ${sign_script} --sign --private-key ${sign_key} --file ${metadata_file} --namespace ${bot_instance}
           # TODO check if signing worked (just check exit code == 0)
           sig_metadata_file=${metadata_file}.sig
           aws_sig_metadata_file=${aws_metadata_file}.sig
diff --git a/scripts/sign_verify_file_ssh.sh b/scripts/sign_verify_file_ssh.sh
index 679ea7d6..2c5717d2 100755
--- a/scripts/sign_verify_file_ssh.sh
+++ b/scripts/sign_verify_file_ssh.sh
@@ -7,6 +7,7 @@
 # Generates a signature file named `<file>.sig` in the same directory.
 #
 # Author: Alan O'Cais
+# Author: Thomas Roeblitz
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -23,25 +24,30 @@
 
 # Usage message
 usage() {
+    local exit_code=${1:-9}
     cat <<EOF
 Usage:
-  $0 sign <private_key> <file>
-  $0 verify <allowed_signers_file> <file> [signature_file]
+  $0 --sign --private-key <private_key> --file <file> [--namespace <namespace>]
+  $0 --verify --allowed-signers-file <allowed_signers_file> --file <file> [--signature-file <signature_file>] [--terse]
 
 Options:
-  sign:
-    - <private_key>: Path to SSH private key (use KEY_PASSPHRASE env for passphrase)
-    - <file>: File to sign
+  --sign:
+    --private-key <private_key>: Path to SSH private key (use KEY_PASSPHRASE env for passphrase)
+    --file <file>: File to sign
+    --namespace <namespace>: Optional, defaults to "file" if not specified
 
-  verify:
-    - <allowed_signers_file>: Path to the allowed signers file
-    - <file>: File to verify
-    - [signature_file]: Optional, defaults to '<file>.sig'
+  --verify:
+    --allowed-signers-file <allowed_signers_file>: Path to the allowed signers file
+    --file <file>: File to verify
+    --signature-file <signature_file>: Optional, defaults to '<file>.sig'
+    --terse: If set, output only matching identity and namespace for verification in JSON format
 
 Example allowed signers format:
-  identity_1 <public-key>
+  identity_1 namespaces="namespace",valid-before="last-valid-day" <public-key>
+
+If the private key has a passphrase, this can be provided via a 'KEY_PASSPHRASE' environment variable.
 EOF
-    exit 9
+    exit "$exit_code"
 }
 
 # Error codes
@@ -50,10 +56,75 @@ CONVERSION_FAILURE=2
 VALIDATION_FAILED=3
 
 # Ensure minimum arguments
-[ "$#" -lt 3 ] && usage
+if [ "$#" -lt 3 ]; then
+    echo "Error: Missing required arguments."
+    usage
+fi
 
-MODE="$1"
-FILE_TO_SIGN="$3"
+# Parse options
+TERSE_MODE=false
+while [[ "$#" -gt 0 ]]; do
+    case "$1" in
+        --sign)
+            MODE="sign"
+            shift
+            ;;
+        --verify)
+            MODE="verify"
+            shift
+            ;;
+        --private-key)
+            PRIVATE_KEY="$2"
+            shift 2
+            ;;
+        --file)
+            FILE_TO_SIGN="$2"
+            shift 2
+            ;;
+        --namespace)
+            NAMESPACE="$2"
+            shift 2
+            ;;
+        --allowed-signers-file)
+            ALLOWED_SIGNERS_FILE="$2"
+            shift 2
+            ;;
+        --signature-file)
+            SIG_FILE="$2"
+            shift 2
+            ;;
+        --terse)
+            TERSE_MODE=true
+            shift
+            ;;
+        *)
+            echo "Error: Invalid argument: $1"
+            usage
+            ;;
+    esac
+done
+
+# Set default namespace if not provided
+if [ -z "$NAMESPACE" ]; then
+    NAMESPACE="file"
+fi
+
+# Ensure mode is set
+if [ -z "$MODE" ]; then
+    echo "Error: Missing operation mode (either --sign or --verify)"
+    usage
+fi
+
+# Ensure required arguments
+if [ "$MODE" == "sign" ]; then
+    [ -z "$PRIVATE_KEY" ] && { echo "Error: --private-key not specified."; usage $FILE_PROBLEM; }
+    [ -z "$FILE_TO_SIGN" ] && { echo "Error: --file not specified."; usage $FILE_PROBLEM; }
+    SIG_FILE="${FILE_TO_SIGN}.sig"
+elif [ "$MODE" == "verify" ]; then
+    [ -z "$ALLOWED_SIGNERS_FILE" ] && { echo "Error: --allowed-signers-file not specified."; usage $FILE_PROBLEM; }
+    [ -z "$FILE_TO_SIGN" ] && { echo "Error: --file not specified."; usage $FILE_PROBLEM; }
+    SIG_FILE="${SIG_FILE:-${FILE_TO_SIGN}.sig}"
+fi
 
 # Ensure the target file exists
 if [ ! -f "$FILE_TO_SIGN" ]; then
@@ -61,8 +132,8 @@ if [ ! -f "$FILE_TO_SIGN" ]; then
     exit $FILE_PROBLEM
 fi
 
-# Use a very conservatuve umask throughout this script since we are dealing with sensitive things
-umask 077 || { echo "Error: Failed to set 0177 umask."; exit $FILE_PROBLEM; }
+# Use a very conservative umask throughout this script since we are dealing with sensitive things
+umask 0077 || { echo "Error: Failed to set 0077 umask."; exit $FILE_PROBLEM; }
 
 # Create a restricted temporary directory and ensure cleanup on exit
 TEMP_DIR=$(mktemp -d) || { echo "Error: Failed to create temporary directory."; exit $FILE_PROBLEM; }
@@ -91,9 +162,7 @@ convert_private_key() {
 
 # Sign mode
 if [ "$MODE" == "sign" ]; then
-    PRIVATE_KEY="$2"
     TEMP_KEY="$TEMP_DIR/converted_key"
-    SIG_FILE="${FILE_TO_SIGN}.sig"
 
     # Check for key and existing signature
     [ ! -f "$PRIVATE_KEY" ] && { echo "Error: Private key not found."; exit $FILE_PROBLEM; }
@@ -102,55 +171,57 @@ if [ "$MODE" == "sign" ]; then
     convert_private_key "$PRIVATE_KEY" "$TEMP_KEY"
 
     echo "Signing the file..."
-    ssh-keygen -Y sign -f "$TEMP_KEY" -P "${KEY_PASSPHRASE:-}" -n file "$FILE_TO_SIGN"
-
-    [ ! -f "$SIG_FILE" ] && { echo "Error: Signing failed."; exit $FILE_PROBLEM; }
-    echo "Signature created: $SIG_FILE"
+    ssh-keygen -Y sign -f "$TEMP_KEY" -P "${KEY_PASSPHRASE:-}" -n "${NAMESPACE}" "$FILE_TO_SIGN"
 
     cat <<EOF
 
 For verification, your allowed signers file could contain:
-identity_1 $(cat "${TEMP_KEY}.pub")
+identity_1 namespaces="${NAMESPACE}",valid-before="LAST_VALID_DAY" $(cat "${TEMP_KEY}.pub")
 EOF
 
+    [ ! -f "$SIG_FILE" ] && { echo "Error: Signing failed."; exit $FILE_PROBLEM; }
+    echo "Signature created: $SIG_FILE"
+
     echo "Validating the signature..."
-    ssh-keygen -Y check-novalidate -n file -f "${TEMP_KEY}.pub" -s "$SIG_FILE" < "$FILE_TO_SIGN" || {
+    ssh-keygen -Y check-novalidate -n "${NAMESPACE}" -f "${TEMP_KEY}.pub" -s "$SIG_FILE" < "$FILE_TO_SIGN" || {
         echo "Error: Signature validation failed."
         exit $VALIDATION_FAILED
     }
 
 # Verify mode
 elif [ "$MODE" == "verify" ]; then
-    ALLOWED_SIGNERS_FILE="$2"
-    SIG_FILE="${4:-${FILE_TO_SIGN}.sig}"
-
     # Ensure required files exist
     for file in "$ALLOWED_SIGNERS_FILE" "$SIG_FILE"; do
         [ ! -f "$file" ] && { echo "Error: File '$file' not found."; exit $FILE_PROBLEM; }
     done
 
-    echo "Verifying the signature against allowed signers..."
-
     # Iterate through each principal in the allowed signers file
-    while IFS= read -r line || [[ -n "$line" ]]; do
-        [[ -z "$line" || "$line" == \#* ]] && continue
-
-        # Extract and process each principal
-        principals=$(echo "$line" | cut -d' ' -f1)
-        IFS=',' read -ra principal_list <<< "$principals"
-
-        for principal in "${principal_list[@]}"; do
-            echo "Checking principal: $principal"
-            if ssh-keygen -Y verify -f "$ALLOWED_SIGNERS_FILE" -n file -I "$principal" -s "$SIG_FILE" < "$FILE_TO_SIGN"; then
-                echo "Signature is valid for principal: $principal"
+    while read -r principal options key
+    do
+        [[ -z "$principal" || "$principal" == \#* ]] && continue
+
+        namespaces=$(echo "$options" | grep -oP "namespaces=\"\K[^\"]+")
+        
+        if [ "$TERSE_MODE" = true ]; then
+            if ssh-keygen -Y verify -f "$ALLOWED_SIGNERS_FILE" -n "$namespaces" -I "$principal" -s "$SIG_FILE" < "$FILE_TO_SIGN" > /dev/null 2>&1; then
+                # Output in JSON format
+                echo "{\"identity\": \"$principal\", \"namespace\": \"$namespaces\"}"
                 exit 0
             fi
-        done
+        else
+            if ssh-keygen -Y verify -f "$ALLOWED_SIGNERS_FILE" -n "$namespaces" -I "$principal" -s "$SIG_FILE" < "$FILE_TO_SIGN"; then
+                echo "Signature is valid for principal: $principal and namespace: $namespaces"
+                exit 0
+            else
+                echo
+                echo "Signature _not_ valid for principal: $principal and namespace: $namespaces"
+            fi
+        fi
     done < "$ALLOWED_SIGNERS_FILE"
 
     echo "Error: No valid signature found."
     exit $VALIDATION_FAILED
-
 else
+    echo "Error: Invalid operation mode. Use --sign or --verify."
     usage
 fi
diff --git a/tasks/deploy.py b/tasks/deploy.py
index 0baa8ee4..37ad3adf 100644
--- a/tasks/deploy.py
+++ b/tasks/deploy.py
@@ -266,6 +266,8 @@ def upload_artefact(job_dir, payload, timestamp, repo_name, pr_number, pr_commen
     metadata_prefix = deploycfg.get(config.DEPLOYCFG_SETTING_METADATA_PREFIX)
     artefact_prefix = deploycfg.get(config.DEPLOYCFG_SETTING_ARTEFACT_PREFIX)
     signing_str = deploycfg.get(config.DEPLOYCFG_SETTING_SIGNING) or ''
+    github = cfg[config.SECTION_GITHUB]
+    app_name = github.get(config.GITHUB_SETTING_APP_NAME)
     try:
         signing = json.loads(signing_str)
     except json.decoder.JSONDecodeError:
@@ -375,6 +377,7 @@ def upload_artefact(job_dir, payload, timestamp, repo_name, pr_number, pr_commen
     cmd_args.extend(['--pr-comment-id', str(pr_comment_id)])
     cmd_args.extend(['--pull-request-number', str(pr_number)])
     cmd_args.extend(['--repository', repo_name])
+    cmd_args.extend(['--bot-instance', app_name])
     cmd_args.extend(sign_args)
     cmd_args.append(abs_path)