This Snapshot was taken from the Deadmau5 Masterclass, proving that Deadmau5 is using this Plugin

In this video, from 3:42 to 3:45, Dyro is using the C4 Multiband Compressor in FL Studio.

In a Facebook video, Wolfgang Gartner is seen using the Waves C4 Multiband Compressor while working on a collaboration with Trina.

"waves bundle fx are very good, we use the C4, the Rcomp, the REQ and the L2 a lot"

This Plugin can be seen at 1:08 in this YouTube video.

At 58:52 in this "Steinberg Studio Sessions EP10 - Deniz Koyu" video Deniz used it.

Used on "Apeshit", as stated by producer Stuart White in this September 2018 Sound on Sound interview.

The first four aux tracks feature SoundToys effects, namely Little Microshift, two EchoBoy delays, and a delay from the Little PrimalTap. Next are a Hall Reverb aux and a Church Reverb aux, both using Waves’ RVerb, an EMT plate from Audio Ease’s Altiverb, four aux tracks with the Waves H-Delay and various other plug-ins on them as well, and four more reverb auxes with the Avid Revibe II, two Avid D-Verbs and another RVerb.

White: “I use the Little Microshift in pretty much every mix, with the left-right micro pitch-shift effect that’s similar to the classic effect in the Eventide H3000 shift where you pitch one side down six cents and one side up six cents to create width. It’s a good way to get your vocals wider without them being out of phase. It thickens up vocals, and is kind of like a doubler. I do quite a lot of filtering on some of the EchoBoy delays, for example with the Waves REQ, and I am adding colour with the SoundToys Devil-Loc, which is great if you want to colour the delay so it is separate from the main vocal, and compress it with the UAD LA3A and mix that in to taste.”

(...) Beyoncé’s lead vocal tracks consist of three aux tracks, four ‘dirty’ and eight ‘clean’ audio tracks. The audio tracks only have the EQ3 on the inserts and a few of them have a send to the Church Reverb. All White’s processing is done on the three aux tracks. “All lead vocals are sent to the ‘B Aux’ track and the ‘B Parra Aux’ tracks. On the former I have the McDSP DS [sic] 555 de-esser. I use the Waves de-esser the most, but in this particular track, because I wanted to compress her voice really hard, I felt that the 555 would work the best. I am rolling off until 6144Hz into what it is detecting; it’s like a side-chain filter. The FabFilter Pro-DS is doing a little more gentle look-ahead de-essing.

“After that there’s some pretty heavy EQ from the EQ3, with a high-pass at 142Hz, a 9dB cut at 244Hz and a 2dB cut at 3kHz. My cut at 244Hz is because she is singing in this husky, low voice, so there’s not a lot of energy in that. I get the energy from the RComp compression, and the EQs, including from the SSL E-Channel, are there to make her sit in the track, rather than making it sound filtered. I love the RComp, mainly because it doesn’t sound like compression to me. The SSL E-Channel adds a bit more compression, and the [Crane Song] Phoenix II Tape Emulation is really cool because while it doesn’t actually sound like tape, it smoothes out transients in a signal just like much analogue equipment does. It enables me to get a fatter vocal sound that again makes the vocal sit in the mix. The final EQ3 has a notch at 3.2kHz to take out some harshness. I also have sends to the Verb aux track, which are the D-Verb and [Waves] H-Reverb, and the Delay 1-4 aux, with the EchoBoy.

The other aux track, ‘B Parra Aux’, is a parallel compression track, with the RCompressor and the CLA 76, which I mixed in low. Both these aux tracks then go to the ‘LD ALL Aux’, on which I’m doing some more surgery with the McDSP AE400 [dynamic EQ], which allows you to set a threshold, just like on a compressor. It’s like turning a volume knob down on a frequency the moment it gets out of control. Finally, there’s the Waves C4, for some control, to keep the vocal even. This track has a lot of energy, so this is an example of using compression for energy, mood and attitude. I also worked a long time to get the compression on Bey’s breaths to pump on the beat. I wanted her breaths to be another percussive element in the track, and getting the attack and release on the compressor right was key to getting that feel and pumping effect.”

Five of the 22 Beyoncé ad lib, backing and harmony vocals below her lead vocals also go to the above-mentioned aux tracks, while the rest have their own signal chains. These audio tracks are sent to several aux tracks, often with tons of plug-ins, and all aux vocal tracks in the end get sent to the ‘Voc All’ group aux right at the top of the session, which has an RCompressor, with ratio at 10:1. There are more group aux tracks, like ‘TrackAux’, ‘FX Voc Aux’, ‘FX’ and ‘Music Aux’, which all get sent to the ‘All Aux’. This in turn gets sent to the ‘no limiter’ mix print track, and finally there’s a Stereo Master track.

Used on "APESHIT", as stated by producer Stuart White in this September 2018 Sound on Sound interview.

The first four aux tracks feature SoundToys effects, namely Little Microshift, two EchoBoy delays, and a delay from the Little PrimalTap. Next are a Hall Reverb aux and a Church Reverb aux, both using Waves’ RVerb, an EMT plate from Audio Ease’s Altiverb, four aux tracks with the Waves H-Delay and various other plug-ins on them as well, and four more reverb auxes with the Avid Revibe II, two Avid D-Verbs and another RVerb.

White: “I use the Little Microshift in pretty much every mix, with the left-right micro pitch-shift effect that’s similar to the classic effect in the Eventide H3000 shift where you pitch one side down six cents and one side up six cents to create width. It’s a good way to get your vocals wider without them being out of phase. It thickens up vocals, and is kind of like a doubler. I do quite a lot of filtering on some of the EchoBoy delays, for example with the Waves REQ, and I am adding colour with the SoundToys Devil-Loc, which is great if you want to colour the delay so it is separate from the main vocal, and compress it with the UAD LA3A and mix that in to taste.”

(...) Jay-Z’s part consists of just two tracks, one lead, and one ad-lib, with an additional ‘reverse’ track, and a ‘jay clean’ track. White: “The main lead vocal track has the SSL E0-channel, Waves C4 multiband compressor for some control, FabFilter Pro-Q2 EQ, with a few notches, and McDSP AE400. Where Jay raps ‘Tell the Grammy’s fuck that 0 for 8 shit / have you ever seen a crowd goin’ apeshit?’, you can hear some stuff in the background, which is another example of me adding flair and energy. That actually comes from the third ‘Voice Sample’ track further up the session, on which I have some automated plug-ins, the ReVibe, Waves S1 Imager, and filter sweep from the EQ3. It’s subtle, but it gives you a little ear candy.”

I had the Waves C4 multi-band compressor on the bass track. That plug-in is a big part of my workflow. It's incredible, I love it. You can tame a track that has a few unruly moments with this plug-in and you're not hearing it work, because it's multi-band.

Sound on Sound article, 2013.

"I am always using the Waves CLA-76 compressor, and the C4 compressor; and I am a huge fan of the Renaissance AXX, especially on guitars – it’s great on electrics, but it’s absolutely phenomenal on acoustics; it’s a really nice, idiot-proof compressor – so straightforward to use. Also, something I call up all the time, especially when Shirley is doing her vocal in the studio, is the Waves RVOX. It works so good. For a fast compressor, you literally just put it on, and pull the threshold down, so it’s kicking down 4 or 5dB, and the peaks are 6dB, and it helps it sit right in the track. Again, it’s just really, really musical, as is all of the Waves kit."

Can be seen being used at 0:55

in this video you can see the Waves C4 running in the top left corner of the screen (you know it's the C4 because of the limited amount of channels in the plugin)