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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-397 2 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 3   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-397 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 5 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 7   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-397 8 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 9   145J TERRA NOVA TELECOM INC. 236   2023-08-06   
301-419 A MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-425 A MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 A MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 0 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 1 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 2 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 3 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 4 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 5 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 6   876D ONVOY, LLC - MD 236   2025-05-10   
301-426 7 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 8 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-426 9 MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-441 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 1 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 2 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 5   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-446 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 8 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-446 9 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-474 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-477 A ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
301-477 0 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-09-15   
301-477 1 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
301-477 2 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
301-477 3 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
301-477 4 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2017-02-01   
301-477 5   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-477 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-477 7 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2015-09-04   
301-477 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2018-01-14   
301-477 9 VINNVACBDS0  876D ONVOY, LLC - MD 236   2018-01-14   
301-479 A WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-479 0 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-11-04   
301-479 1 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-479 2   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-479 3 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      

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Last updated: Sun, 17 May 2026 03:26:51 UTC

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