diff --git a/core/config.py b/core/config.py
index 7940525..9218951 100644
--- a/core/config.py
+++ b/core/config.py
@@ -19,18 +19,6 @@ with open("config.yml") as f:
     config = yaml.safe_load(f)
 logger.info("Loaded config.")
 
-# Warn about config keys that were renamed from "sig" to "activity" in Spothole v3, as these will otherwise be silently
-# ignored.
-if "sig_ref_data_providers" in config:
-    logger.warning(
-        'Your config file contains "sig_ref_data_providers", which was renamed to "activity_ref_data_providers" in Spothole v3. Please update your config.yml, otherwise no activity reference data will be loaded.'
-    )
-for _entry in config.get("spot_providers", []):
-    if "sig" in _entry or "sig_ref_prefix" in _entry:
-        logger.warning(
-            f'Your config file contains "sig" or "sig_ref_prefix" for the {_entry.get("class")} spot provider. These were renamed to "activity" and "activity_ref_prefix" in Spothole v3. Please update your config.yml.'
-        )
-
 BASE_URL = config.get("base_url", "http://localhost:8080")
 MAX_SPOT_AGE = config.get("max_spot_age_sec", 3600)
 MAX_ALERT_AGE = config.get("max_alert_age_sec", 604800)
diff --git a/core/status_reporter.py b/core/status_reporter.py
index 3fd1ff2..41f9612 100644
--- a/core/status_reporter.py
+++ b/core/status_reporter.py
@@ -111,8 +111,6 @@ class StatusReporter:
             }
             for p in DATA_PROVIDERS.static_data_providers
         ]
-        # Remove the old name for this key if it's still present in status data persisted by Spothole v2 and earlier
-        DATA_STORE.status.get().pop("sig_ref_data_providers", None)
         DATA_STORE.status.get()["activity_ref_data_providers"] = [
             {
                 "activity_name": p.activity_name,
diff --git a/static/js/common.js b/static/js/common.js
index e62111c..700514a 100644
--- a/static/js/common.js
+++ b/static/js/common.js
@@ -33,16 +33,6 @@ function saveSettings() {
 // Load settings from local storage and set up the filter selectors. Suppressed if "use local storage" is false.
 function loadSettings() {
     if (useLocalStorage) {
-        // Spothole v2 and earlier stored activity filter settings with "sig" in the element IDs, so migrate these to
-        // their new names.
-        Object.keys(localStorage).forEach(function (key) {
-            if (key.startsWith("#filter-button-sig-")) {
-                const newKey = key.replace("#filter-button-sig-", "#filter-button-activity-").replace("-NO_SIG:", "-NO_ACTIVITY:");
-                localStorage.setItem(newKey, localStorage.getItem(key));
-                localStorage.removeItem(key);
-            }
-        });
-
         // Find all local storage entries and push their data to the corresponding UI element
         Object.keys(localStorage).forEach(function (key) {
             if (key.startsWith("#") && key.includes(":")) {
@@ -78,11 +68,6 @@ function loadURLParams() {
     updateSelectFromParam(params, "max_age", "max_spot_age"); // Only on Map & Bands pages
     updateFilterFromParam(params, "band", "band");
     updateFilterFromParam(params, "activity", "activity");
-    // Spothole v2 and earlier called the "activity" param "sig", so support this for existing embeds
-    if (params.get("activity") == null && params.get("sig") != null) {
-        params.set("activity", params.get("sig").replace("NO_SIG", "NO_ACTIVITY"));
-        updateFilterFromParam(params, "activity", "activity");
-    }
     updateFilterFromParam(params, "source", "source");
     updateFilterFromParam(params, "mode", "mode");
     updateFilterFromParam(params, "dx_continent", "dx_continent");