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Multicast Groups No Joins

Hi all.  I have a multi layer switch acting as a router for inter vlan traffic between L2 switches.  Currently the MLS has ip multicast-routing globally, ip sparse-dense-mode on VLANs, and no specified multicast groups.  I see multicast group  on multiple VLANs, but not a single source.  I'd like to remove ip sparse-dense-mode from these VLANs as I don't see the need for it.  Based on the output below is it safe to say there are no end user interested in this multicast traffic? 

45001-E1-CORESW1#sh ip igmp groups
IGMP Connected Group Membership
Group Address    Interface                Uptime    Expires   Last Reporter   Group Accounted    Vlan800                  3w3d      00:02:17    Vlan600                  18w3d     00:02:17    Vlan100                  18w2d     00:02:32


45001-E1-CORESW1#show ip igmp groups detail

Flags: L - Local, U - User, SG - Static Group, VG - Virtual Group,
       SS - Static Source, VS - Virtual Source,
       Ac - Group accounted towards access control limit

Interface:      Vlan800
Uptime:         3w3d
Group mode:     EXCLUDE (Expires: 00:02:40)
Last reporter:
Source list is empty

Interface:      Vlan600
Uptime:         18w2d
Group mode:     EXCLUDE (Expires: 00:02:40)
Last reporter:
Source list is empty

Interface:      Vlan100
Uptime:         18w2d
Group mode:     EXCLUDE (Expires: 00:02:31)
Last reporter:
Source list is empty

45001-E1-CORESW1#sh ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
       L - Local, P - Pruned, R - RP-bit set, F - Register flag,
       T - SPT-bit set, J - Join SPT, M - MSDP created entry, E - Extranet,
       X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
       U - URD, I - Received Source Specific Host Report,
       Z - Multicast Tunnel, z - MDT-data group sender,
       Y - Joined MDT-data group, y - Sending to MDT-data group
       V - RD & Vector, v - Vector
Outgoing interface flags: H - Hardware switched, A - Assert winner
 Timers: Uptime/Expires
 Interface state: Interface, Next-Hop or VCD, State/Mode


(*,, 7w0d/00:02:51, RP, flags: SJC
  Incoming interface: Null, RPF nbr
  Outgoing interface list:
    Vlan100, Forward/Sparse-Dense, 18w3d/00:03:18

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