| GR-book# | Pg# | Instr. # | Surname | Given Names | Residence | Instr. Date | Reg Date | Death Date | Type of Instr. |
| 6 | 30 | 965 | MANSON | Samuel Ryckman | Hamiton | 1916-10-20 | 1916-11-16 | Power of Attorney | |
| 6 | 109 | 1011 | MARCOTTE | Joseph Oswald | Steelton | 1913-04-17 | 1917-07-23 | Power of Attorney | |
| 4 | 416 | 588 | MARKS | Mary Elizabeth | Port Arthur | 1907-07-03 | 1909-10-18 | Power of Attorney | |
| 4 | 418 | 589 | MARKS | Mary Elizabeth | Port Arthur | 1907-07-03 | 1909-10-18 | Power of Attorney | |
| 3 | 102 | 223 | MARKS | Thomas | Thunder Bay | 1900-06-06 | 1900-07-09 | Property Sale | |
| 4 | 7 | 385 | MARRINER | Mary A. | Sault Ste. Marie,ON | 1902-10-11 | 1902-10-20 | Power of Attorney | |
| 11-2nd | 598 | 2955 | MARSHALL | Lucy & William H | Korah Twp. | 1916-12-12 | 1940-11-05 | Alimony | |
| 12 | 168 | 3205 | MARSHALL | Harry Harbour | Owen Sound | 1943-05-22 | 1943-05-31 | Custody | |
| 4 | 119 | 419 | MARSHALL | Mary Ann | Toronto | 1902-04-10 | 1903-06-23 | Power of Attorney | |
| 12 | 646 | 3575 | MARUSYK | William | Richmond, B.C. | 1946-05-15 | 1946-06-18 | Power of Attorney | |
| 12 | 210 | 3238 | MASON | Richard Faux | Sault Ste. Marie, ON | 1943-09-04 | 1943-09-09 | Power of Attorney | |
| 5-1st | 78 | 673 | MAYBERRY | Alfred W. | Moosejaw, Sask | 1911-07-05 | 1911-07-20 | Power of Attorney | |
| 3 | 126 | 247 | MAZZUEA | Giovanni | 1900-08-22 | 1900-08-23 | Mechanic Lien | ||
| 5-2nd | 587 | 938 | McAULEY | John Thomas | Blind River | Adm | 1916-05-02 | 1915-11-12 | Power of Attorney |
| 5-1st | 161 | 716 | McCAIG | Ellen | Collingwood | 1912-04-24 | 1912-05-04 | Co-executor | |
| 7-2nd | 470 | 1456 | McCAIG | Mary & Margaret | Collingwood | 1922-04-17 | 1922-06-20 | Power of Attorney | |
| 9-1st | 103 | 1890 | McCARTHY | James | Sault Ste. Marie, ON | 1924-06-13 | 1928-03-27 | Power of Attorney | |
| 4 | 149 | 443 | McCLURE | John | 1904-02-24 | 1904-02-27 | Mechanic Lien | ||
| 9-2nd | 442 | 2050 | McCREA | Elizabeth | Day Twp. | 1929-11-09 | 1929-11-15 | Power of Attorney | |
| 5-2nd | 405 | 837 | McCREIGHT | John | Kelvinhurst, Sask | 1913-07-25 | 1914-07-07 | Power of Attorney | |
| 5-2nd | 286 | 765 | McCREIGHT | John | Thessalon | 1912-10-17 | 1913-03-12 | Power of Attorney | |
| 5-2nd | 410 | 839 | McCREIGHT | Martha Jane | Kelvinhurst, Sask | 1913-07-25 | 1914-07-13 | Power of Attorney | |
| 3 | 1 | 173 | McCULLOCH | Robert | Korah Twp. | 1898-04-14 | 1898-04-14 | Indenture | |
| 3 | 234 | 312 | McDONALD | Daniel Robert | 1901-03-29 | 1901-03-29 | Discharge of Mech. Lien | ||
| 3 | 22 | 186 | McDONALD | Alexander G. | Port Arthur | 1898-01-03 | 1899-05-22 | Indenture | |
| 3 | 222 | 306 | McDONALD | Donald Robert | 1901-03-06 | 1901-03-06 | Mechanic Lien | ||
| 3 | 206 | 296 | McDONALD | D. R. | 1901-01-05 | 1901-01-01 | Mechanic lien | ||
| 3 | 230 | 308 | McDONALD | Frances | Sault Ste. Marie, ON | 1901-02-28 | 1901-03-15 | Power of Attorney | |
| 6 | 90 | 1000 | McDONALD | Annie Jane | Trail Village,Oregon | 1917-05-29 | 1917-07-12 | Power of Attorney | |
| 4 | 123 | 422 | McDOUGAL | Alexander | Day Twp. | 1901-01-28 | 1903-07-09 | Mechanic Lien | |
| 7-2nd | 502 | 1473 | McFADDEN | Ada | Sault Ste. Marie,ON | 1922-09-05 | 1922-09-13 | Power of Attorney | |
| 6 | 96 | 1004 | McFARLAND | George Franklin | Toronto | 1916-10-03 | 1917-06-21 | Power of Attorney | |
| 4 | 384 | 565 | McFARLANE | William James | Toronto | 1909-02-06 | 1909-03-19 | Power of Attorney | |
| 4 | 457 | 610 | McKAY | John | Sault Ste. Marie,ON | 1909-07-13 | 1910-04-18 | Power of Attorney | |
| 3 | 126 | 246 | McKEACHNIE | Ella | 1900-08-23 | 1900-08-23 | Mechanic Lien | ||
| 3 | 145 | 267 | McKECHNIE | Bennett | Sault Ste. Marie, ON | 1900-10-05 | 1900-10-06 | Discharge of Mechanic Lien | |
| 3 | 132 | 257 | McKECHNIE | W. E. | 1900-09-01 | 1900-09-04 | Mechanic Lien | ||
| 6 | 323 | 1115 | McKINNON | Charles A. | Sault Ste. Marie,ON | 1918-10-15 | 1918-10-31 | Mortgage | |
| 3 | 370 | 362 | McKINNON | Elizabeth Charlott | Woodville, Victoria Co. | 1902-04-23 | 1902-05-16 | Power of Attorney | |
| 7-2nd | 577 | 1516 | McKINNON | Elizabeth Charlotte | Vancouver | 1923-05-01 | 1923-06-29 | Power of Attorney | |
| 7-2nd | 564 | 1508 | McKINNON | Elizabeth C. | Vancouver | 1923-05-17 | 1923-05-23 | Power of Attorney | |
| 13-nd | 3821 | McLEOD | Anestos E. & Nellie | Champlain, Quebec | 1945-11-02 | 1848-06-19 | Power of Attorney | ||
| 11-1st | 184 | 2686 | McLURG | Mary E. | Sault Ste. Marie, ON | 1937-10-05 | 1937-10-06 | Dis Power of Attorney | |
| 10-2nd | 689 | 2532 | McLURG | Mary E. | Sault Ste. Marie,ON | 1935-03-25 | 1936-03-24 | Power of Attorney | |
| 10-1st | 226 | 2247 | McMILLAN | Rosanna | Sault Ste. Marie,ON | 1932-02-08 | 1932-02-08 | New Executive | |
| 5-2nd | 583 | 936 | McNALLY | George A. | Sault Ste. Marie,ON | 1916-05-12 | 1916-05-22 | Power of Attorney | |
| 4 | 495 | 635 | McNAMARA | James & Josephine | St. Ignace | 1909-02-23 | 1919-10-01 | Power of Attorney | |
| 3 | 41 | 192 | McNIECE | James | Chapleau | 1899-07-01 | 1899-08-04 | Indenture | |
| 3 | 145 | 267 | McPHAIL | John | 1900-10-05 | 1900-10-06 | Discharge of Mechanic Lien | ||
| 8-2nd | 376 | 1719 | McPHAIL | Christina | Sault Ste. Marie,ON | 1925-04-14 | 1926-01-05 | Power of Attorney | |
| 4 | 459 | 612 | McRAE | Mary Emma Eliza | Weston, York Co. | 1910-02-12 | 1910-04-28 | Power of Attorney | |
| 4 | 374 | 562 | McRAE | Mary E. E. | Gore Bay | 1890-03-03 | 1909-02-22 | Power of Attorney | |
| 13-1st | 3703 | McRAE | Velma Morgan | Culefernie | 1945-08-23 | 1947-05-23 | Power of Attorney | ||
| 3 | 240 | 315 | MEAGHER | P. F. | Sault Ste. Marie, ON | 1901-04-01 | 1901-04-01 | Discharge of Mech. Lien | |
| 3 | 155 | 274 | MEAGHER | P. F. | 1900-10-27 | 1900-10-27 | Mechanic Lien | ||
| 8-2nd | 297 | 1676 | Mercantile Trust Co. | Canada | 1924-12-15 | 1925-05-25 | Indenture | ||
| 8-2nd | 459 | 1766 | METZGER | William E. | Detroit | 1926-06-09 | 1926-09-18 | Power of Attorney |