diff --git a/data/as-block/AS1-AS4294967294 b/data/as-block/AS1-AS4294967294
index d9d7fafb1..a99bd8288 100644
--- a/data/as-block/AS1-AS4294967294
+++ b/data/as-block/AS1-AS4294967294
@@ -2,6 +2,6 @@ as-block:           AS1-AS4294967294
 descr:              Root AS-BLOCK
 remarks:            This block is reserved to delegate access for sub-allocations.
 remarks:            You can not freely register any ASN in this block.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             closed
 source:             DN42
diff --git a/data/as-block/AS4242420000-AS4242423999 b/data/as-block/AS4242420000-AS4242423999
index 94b826a66..bc01066a7 100644
--- a/data/as-block/AS4242420000-AS4242423999
+++ b/data/as-block/AS4242420000-AS4242423999
@@ -3,6 +3,6 @@ descr:              dn42 ASN space for end-users
 remarks:            This block is reserved for end-users allocation.
 remarks:            You can freely register any ASN in this block.
 remarks:            However, please don't allocate sub-blocks in this ASN space.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             open
 source:             DN42
diff --git a/data/as-block/AS4242424000-AS4242426999 b/data/as-block/AS4242424000-AS4242426999
index 6d1b8c7fd..94acc859a 100644
--- a/data/as-block/AS4242424000-AS4242426999
+++ b/data/as-block/AS4242424000-AS4242426999
@@ -1,6 +1,6 @@
 as-block:           AS4242424000-AS4242426999
 descr:              Future dn42 use
 remarks:            This block is reserved for future dn42 use.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             closed
 source:             DN42
diff --git a/data/as-block/AS4242427000-AS4242429999 b/data/as-block/AS4242427000-AS4242429999
index 94903c351..2e1c19304 100644
--- a/data/as-block/AS4242427000-AS4242429999
+++ b/data/as-block/AS4242427000-AS4242429999
@@ -2,6 +2,6 @@ as-block:           AS4242427000-AS4242429999
 descr:              dn42 ASN space for sub-allocations
 remarks:            This block is reserved for sub-allocations.
 remarks:            Please don't allocate individual ASN directly in this block.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             ask
 source:             DN42
diff --git a/data/as-block/AS64512-AS65534 b/data/as-block/AS64512-AS65534
index e8bae02df..4fcd0695e 100644
--- a/data/as-block/AS64512-AS65534
+++ b/data/as-block/AS64512-AS65534
@@ -1,5 +1,5 @@
 as-block:           AS64512-AS65534
 descr:              Private ASN block
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             closed
 source:             DN42
diff --git a/data/as-block/AS64600-AS64855 b/data/as-block/AS64600-AS64855
index 262ab6c61..5bef955bf 100644
--- a/data/as-block/AS64600-AS64855
+++ b/data/as-block/AS64600-AS64855
@@ -3,6 +3,6 @@ descr:              dn42 native ASN block (legacy)
 remarks:            The legacy policy was that if you own 172.22.x.0/24 you own the ASN 64600+x.
 remarks:            With the default allocation policy of an /25 per person now this becomes a problem.
 remarks:            Please only make an assignment from this block if you can't use 4 byte ASNs.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             ask
 source:             DN42
diff --git a/data/as-block/AS64856-AS64999 b/data/as-block/AS64856-AS64999
index 39dcd7a4b..4ac8ec9d4 100644
--- a/data/as-block/AS64856-AS64999
+++ b/data/as-block/AS64856-AS64999
@@ -3,6 +3,6 @@ descr:              dn42 native ASN block (legacy)
 remarks:            this block was allocated to encourage people to use the private AS range reserved
 remarks:            by IANA instead of the 76100-76199 block.
 remarks:            Please only make an assignment from this block if you can't use 4 byte ASNs.
-mnt-by:             DUMMY-MNT
-policy:             open
+mnt-by:             DN42-MNT
+policy:             closed
 source:             DN42
diff --git a/data/as-block/AS76100-AS76199 b/data/as-block/AS76100-AS76199
index 999bef7ab..37a88f15e 100644
--- a/data/as-block/AS76100-AS76199
+++ b/data/as-block/AS76100-AS76199
@@ -4,6 +4,6 @@ remarks:            This range was never intented to be used as private ASN
 remarks:            space by IANA.  Rather, it is part of a larger block of
 remarks:            "reserved" AS numbers.
 remarks:            The use of this block is now strongly discouraged.
-mnt-by:             DUMMY-MNT
+mnt-by:             DN42-MNT
 policy:             closed
 source:             DN42