The staff at Signature Investigations Group is second to none. I have been in HR for 17 years and used over 5 different Private Investigators. After speaking to Mike and Courtney, I knew why they called themselves Professional Investigators. I was happy to see that Signature Investigations has multiple woman investigators who also are qualified as professionals!

The fact that we could have someone other than a man work our case was the original deciding factor, but soon realized their capabilities of accomplishing what was near impossible before, seemed to be just another day in their world. Their case managing took me a few phone calls to understand, but Mike replied to a voicemail on a Sunday afternoon.
We have utilized them from everything from Workers' Compensation, Employee Misconduct and Employee Discharge Investigations, and soon Mike and his team will be approved by our vendors for Intellectual Property Investigations. Signature Investigations is a true example of you get what you pay for.

Heidi - HR Manufacturing Company

Central MI (January 2018)

Mike is honestly amazing!! No one was willing to help us in the situation we were in and we contacted him and within an hour he sent us the information we needed and said "sorry it took so long" WE WERE BLOWN AWAY! We did not expect for him to be that quick. Truly truly worth every penny and he is so nice and professional. There are so many great things to say about him, if you need help CALL HIM!!

Kristin W

Whitehall (August 2017)

There may come a time in your life, or your business, that requires that something, or someone, be investigated. When that time comes, I recommend you use the professional services of Signature Investigations Group. I have known the people associated with this company for many years and know them to be highly ethical and thorough in all aspects of their work. The Law Office of Richard J. Stolcenberg highly recommends them for any of your needs.

Richard Stolcenberg, Attorney

Grand Rapids, MI

I met Mike when I owed my own firm. Right away, I knew he was a trustworthy professional. Every time I need something investigated, Signature Investigations Group delivers for my clients and me. Mike does not sit on a matter. His team acts quickly. Mike's insights are keen, his fieldwork is thorough, and his reports are clear. Based on my experience, I trust Signature Investigations Group with my clients' matters, and you can, too.

Nathaniel Kaleefey


"I have known Mike for several years. I have never needed his services untilI was in a situation where a business partner wanted/insisted I buy him out. I called Mike on a Sunday evening and by Monday morning, I had learned that my partner had bought a home in Texas a few months before. A few hours later, Mike called to tell me my partner already has another business in Texas. All of which were a surprise to me. With this knowledge, I was able to confront my partner since we were in a contract. I was able to buy his shares for much less and saved several thousand dollars. Not only is Mike a good friend, but quick to reply to an issue and took my situation serious. Mike now does all of my background checks for employment. Mike will be any small business owner's friend. Keep his number."

Tim R.

Petoskey, MI

"Mike worked directly on my case which I was thrilled with. I was able to find our babysitter did not care for our daughter in a timely manner and was able to replace her immediately. My husband and I both recommend his services to all parents."

Jody M.

Grand Haven, MI

"If it wasn't for Mike's determination, I would have continued my engagement to my fiancé. Mike uncovered her debt that she had told me was paid and unflattering inability to stay faithful. It took him awhile to come up with all of the evidence, but with Mike's communication and explanation, I was able to detect statements that weren't true and kept him working until we found the truth. I am thankful he kept on his suspicion, but it was a hard pill to swallow. But I am now involved with a new lady and she passed the background check and the Matt check. I will be getting engaged soon if she accepts."

Matt T.

Kentwood, MI

"Mike has worked several times for us and we always know we will get quick, precise and accurate reports and video evidence in our Workman's Comp cases. Thank you for not wasting our time and getting to business."

Ryan T.

Grand Rapids, MI (Midsize West Michigan Corporation)

"I have used Mike's background checks for my lawn care business. I happened to see him at a hockey game and started telling him about my sister's possible use of my mother's money. We negotiated a fair fee and within 2 days, I had proof my mother's estate was paying for my sister's utilities. Regrettably I had to have my attorney get involved, but his services saved my mother's estate for all of her children and grandchildren."

Ben C.

Holland, MI

"When approached for a job offer that sounded too good to be true in this economy, I asked Mike to check them out. There are too many scams and people preying on others these days, but Mike came back letting me know it was a legitimate business. This was invaluable to me, and I now have my perfect position! I would highly recommend Mike to anyone in my situation."

Kate Y.

Grand Rapids, MI

We Utilized Signature Investigations on a Custody Case for my husband. They found out my husband's daughter was staying in a home where there were several dozen marijuana plants for a medical marijuana dispensary. The surveillance they did showed several cars coming and going and even showed some of the equipment. We made immediate contact with authorities and owe it all to them. Thank you so much for caring and not giving up.

Julie S.

Grandville, MI

Great communication. Very professional team. Thank you guys for your help and the gps tracking reports were the icing on the cake. A very satisfied client.

Matt B.

Grand Rapids, MI

The entire "H" family would like to say THANKS to Signature Investigations Group, I was able to confirm my worst fears about our son's custody visits to his father's home in Kent City. We didn't just want to hire anyone, so after asking an attorney and reading reviews, we chose Mike and his team. With the evidence they secured over a 2 week period, we were able to renegotiate the terms of our custody. I was nervous at first as I have never hired a private investigator, but it has put our minds to rest. Words will never express the gratitude for helping us keep my son safe.

Mary H.

Nashville, TN

Michael's work product was excellent -- thorough, and well organized. He was available to take my calls after normal business hours. Mike also stands out in his commitment to confidentiality -- something that my profession absolutely demands.

Nick Caputo

Attorney at Law

Mike has been a great resource for our law firm. I contacted Mike in a crunch. Not only did he responded to my request promptly, but he provided us with a great work product.

Jordan C. Hoyer


I highly recommend Michael and Signature Investigations Group for any investigative services. As a recent client, he went above and beyond to make sure I received the information I needed. He did a thorough job, putting forth extra effort to make sure his information was accurate. I will certainly hire him again without question if the need arises. Thank you, Michael... for helping me and being GREAT at what you do!

Tiffany C

Michael goes above and beyond to achieve results without compromising his high morals and standards. A true professional.

Nicholas Schouten

Principal Investigator / Maxwell-Jade Inc.

We have hired Signature Investigations on several occasions as we conduct background checks on new employees. Michael is very personable, easy to work with and he will recommend which services will work best for you or your company. He is very thorough and fast.

Shannon M

Positive: Professionalism
I thought I was going crazy when my fiancé kept asking about conversation I had with other people in my condo. I hired Signature Investigations and Mike and his people checked for bugs and cameras the same day. They found one in my 13 year old daughter's bedroom and one in my closet. When I broke down crying Mike helped me to call law enforcement. I felt vindicated and was able to prove to our families I wasn't crazy and worth twice what I paid. I learned a lot when they did the bug sweep. Mostly that I was too trusting.

Lisa R

Mike and his team are proficient very thorough and get Pertinent information in a timely fashion. They are so professional and truly care. If you need help I promise you look no further. You will not be disappointed. These people know their stuff and they are awesome!! Can't thank them enough!!


Positive: Professionalism, Quality, Responsiveness, Value
Awesome!!!!! This guy is top notch! Honest!

Kriss W

Mike and Signature Investigations are amazing people to work with up front and honest and are very quick to get it done and get all the information that you need and make sure it is accurate.

Aaron M

Very thorough and professional. Exceeded my expectations. I definitely recommend Signature Investigations. Thanks Mike.

Greg V

When it comes to GPS technology and incorporating the
technology into an investigation and investigative business,
Mike Cook from Signature Investigation Group is one of the most knowledgeable in the Midwest.

Mike has always been a go-to person to answer any
questions regarding GPS devices and how an investigator
can use and detect these devices.

George Gergis - Licensed Professional Investigator

Mike and Signature Investigations were wonderful to work with. He allowed us to have a great sense of security in an otherwise very stressful and unsettling time. He was easy to reach and returned all correspondence promptly. We are very grateful that such a service exists and we are so very pleased with the experience of working with this company.

Kate D

Signature Investigations Group and Mike were on top of our case from the moment we said go. Not only did they save us very large sums of money on a Due Diligence case by helping determine the company was not what it seemed on paper, Mike was so well connected, he put us in touch with a replacement.

Professionalism is hard to find, but this company and all of their employees push it to the forefront.

Update. 11/20/2018.
We just used Signature again and within 3 days they were able to determine how a competitor was getting information about our bids. This will save us tens of thousands of dollars. Mike and his team have the answers. Thank you once again!

Doug G

Update. 07/12/2019
Signature's Team was amazing in court. Not only did we win, the judge reminded the defendants 5 times that we had all the proof they were in cahoots with our competition. This was a huge WIN.


I would recommend Mike from signature Investigations. He did a great job for me, and in a timely manner. Keep up the good work Mike.

Kevin B

5 stars!

Jill S

Mike and his staff we're terrific, and worked hard to solve my domestic situation. Highly recommend them as they will surly bend over backwards to find the answers to your questions.

Joseph M

We hired them to find someone and serve them. Mike was fantastic, friendly and thorough.
Although we wanted to call every hour we let them do their job and they did. Thank you again from the bottom of our hearts. You guys did great

Rose M

Mike, thank you for all you and your team have done to help our family! You've been responsive, compassionate and transparent. We will recommend you to anyone who needs investigative services.

If you want to use this as an endorsement for your website please do!


When you work with Signature Investigations your information remains 100% confidential.

We proudly serve the following cities, and more!

Grand Rapids | Holland | Muskegon | Kalamazoo | Lansing | Detroit | Traverse City | Mt. Pleasant | Kentwood | Ada | Big Rapids | Battle Creek | Flint | Ann Arbor | Marquette | St. Ignace | Rockford | Ludington | Southfield | Jackson | Newaygo