Transcript for Kate Upton talks sexual misconduct allegations and reveals details of incident with Guess co-founder
We begin with an ABC news exclusive. Supermodel Kate Upton is here live in our studio. She's going to talk about those accusations of sexual misconduct against guess co-founder Paul Marciano. We're going to speak to Kate in just a moment but first a closer look at the allegations and what has followed. Before "Sports illustrated" made her into a cover girl -- ??? I got a fever ??? Reporter: At roles in commercials and movies transformed her into a superstar. What's going on? Reporter: Kate Upton was just starting out in this guess campaign. Now alleging that guess co-founder Paul Marciano sexually and emotionally harassed her. Upton provided details of the alleged assault to "Time" magazine. Saying that at a lingerie shoot when she was just 18, Marciano grabbed my breasts and started feeling them. After I pushed him away he said, I'm making sure they're real. Then she told the magazine, he grabbed the back of my head so I could not move and started kissing my face and my neck. Upton claims she was harassed and insulted in UBS scent shoots alleging Marciano once called her a fat pig. A photographer that worked with her on some of the shoots corroborated her account to ABC news and says he stands with Kate. But Marciano denies her claims calling them preposterous and saying he's never been alone with the model and never touched her inappropriately. I fully support the me too movement. At the same time I will not allow others to defame mean's tarnish my reputation. On Thursday her husband, Justin Verlander saying he's proud of Upton and I know Thi difficult decision to tell her story is to empower others in similar situations and also to encourage those who witness this behavior to speak out to create change. That is what the me too movement is all about. #Thanky #thankyoukate. And Kate Upton joins us live. I know you're having deep breaths here. Yes, exactly. How are you? I'm doing good. You know what, I'm actually really excited about sharing my movement. As soon as I did my article with "Time" I felt a sense of relief because it's a new climate. Women are coming together and they're able to have that platform to share your story and create real change for her women and for this tri and for the better. That's why you decided to do it now because people were wondering why the moment, why right now? Yeah, you know, I was going back and forth about sharing this story because it's always easier to leave things in the past. But actually what gave me the push to do it is I did a workout with a lot of new models for fashion week since it was their first fashion week and a lot of girls were sharing how excited they were about the different opportunities they got and the start of their career and I remembered being in that place whenever I got the meeting to go meet with Paul Marciano and how different my view of the industry after that meeting was and I wanted to prevent that from happening for these other girls who are just starting out. Because you were 18 at the time. Yes. You said this happened. You're only 25 now. You said it has had a real impact. It did. It had a huge emotional impact after because it made me question what I was doing, what I was -- how I was putting myself out there to be treated in this way, you know, I'm thinking I walked into a professional meeting and I thought I was carrying myself in a professional way. How did this treatment happen to me? And you start blaming yourself and you try to change yourself. I started slumping my shoulders, wearing baggier clothes. And I had to go through this moment where I was like, that's not my fault. That's his fault that is his way of acting and I had to empower myself again. Did you tell anybody at the time? We do have a photographer that says that he was there because Paul Marciano claims that he was never alone with you and you said that was not the case. It happened in front of other people. Yeah, exactly. I agree with him. We were never alone together and I made sure of it. You know, for the meeting that we -- I came in with the photographer Yu Tsai because we were going to talk about the possibility of shooting the nex campaign all together. And he did it right in front of him and after that I had to come up with a lot of different strategies to make sure I wasn't in the same room with him alone. He has flat out denied. He said this did not happen. Other men when they are accused, they will point out certain points, but Paul Marciano has said, absolutely false. Yeah, well, you know, honestly I don't really need his validation for what happened so I'm not looking for him to come forward and tell the truth and honestly I expected him to do that and I think it speaks to how he's treated these allegations in the past and it used to work before but that's not the case anymore and we're being heard and our stories are taken seriously and I think that that speaks to the culture change that needs to happen within corporate offices. And I know because you had also said and many people have also said it's not just the person who allegedly makes these -- this misconduct and worse, but it's those enablers and people who are aware of it. Paul Marciano says that he welcomes an investigation of -- and will cooperate fully in an investigation with guess. Would you do the same in being involved in an investigation? Yes, I think it's really important and honestly I think that it would be so nice to see big corporations and businesses doing this on their own, having investigations and looking into their offices on their own without victims needing to come forward because we already know there is a huge imbalance of power within businesses and so I think it's really important for employees and for everyone to be educated on exactly what sexual harassment is and what consent means so that everyone feels safe inside their professional setting and everyone feels confident in how they're treating each other, men and women. Has guess or anybody from guess contacted you since the article, since you coming -- No, they have not. Would you want to speak with anybody there? I think if it bettered their investigation, yes, but I really have no need to speak to them. So what would you like to see happen next, Kate? Next I would love for people around these people to come out so they're not neighboring them and so that victims not only have to live through this and then relive it again when they come out with their story, but they shouldn't be also expected to change the entire culture inside all these corporations and businesses. It should be the people around wanting to make the workplace better, wanting to give everybody equal opportunities. And what can you say to people who will can't seem to fully understand, this was not easy for you to come forward. Tight. I mean I've been around you enough to know this is not an easy conversation for you to have but it's one that you feel is very important. What do you say to people who say, well, why now? Why didn't you say something then when it first happened? Can you help them understand the difficulty? Yeah, well, you know what, because it was a completely different world then when it happened. You were -- and I was 18 years old and everybody around me is telling me to -- well, they're not telling me but they're pushing me to not tell my story, it's better to keep things in the dark or, you know, just go because everyone is inc by me getting on set, the agents, everybody gets paid if I show up on set. So you're con aptly pushed to show up on set no matter what happens and they're bringing up examples of other women who are fine with this behavior and have really successful careers so you're subtly being pushed to be there and then you're also having doubt in your mind of how I acted. Did I ask for this treatment? But you didn't. This is their behavior and I think that the women who came out before and after me really prove that. Paul's pattern is -- Now you're one of those women who have come forward and saying me too and I know the support of Justin, we saw what he tweeted and your family, that has to mean so much. It means the world to me. You know, from the very beginning my family and my husband all supported me and were really proud of me for coming out and telling my story, because it is hard to do. It is hard to admit that that happened. Well, we appreciate your willingness to come here this morning and share your story with us, Kate. Thank you so much. We wish you all the best and I know it's fashion week and hopefully there will continue to be changes. Exactly. Thanks so much. Thank you.
This transcript has been automatically generated and may not be 100% accurate.