diff --git a/src/georinex/nav3.py b/src/georinex/nav3.py
index d0758c3..d3947d2 100644
--- a/src/georinex/nav3.py
+++ b/src/georinex/nav3.py
@@ -135,7 +135,7 @@ def rinexnav3(
             if len(nav) == 0:
                 nav = xarray.Dataset(dsf, coords={"time": tu, "sv": [svv]})
             else:
-                nav = xarray.merge((nav, xarray.Dataset(dsf, coords={"time": tu, "sv": [svv]})))
+                nav = xarray.merge((nav, xarray.Dataset(dsf, coords={"time": tu, "sv": [svv]})), compat="override", join="outer")
 
             sv_copies += 1
             check[np.arange(check.size)[check][iu]] = False